Beginning Computer I - Glossary

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The Ethernet standard for local area networks using twisted-pair cable carrying data at 100 megabits per second (Mbps).


The Ethernet and IEEE 802.3 standard for baseband local area networks using a thin coaxial cable up to 200 meters long and carrying data at 10 megabits per second (Mbps). Cables connect to network adapters by a BNC connector.


The Ethernet standard for local area networks using twisted-pair cable carrying data at 10 megabits per second (Mbps).



Describes the window or icon that you are currently using or that is currently selected. The operating system always applies the next keystroke or command you choose to the active window. Windows or icons on the desktop that are not selected are inactive.

See also: channel

active content

Dynamic content, such as a stock ticker, a weather map, or news, that is usually updated from the World Wide Web or a channel.

Active Directory

The directory service that stores information about objects on a network and makes this information available to users and network administrators. Active Directory gives network users access to permitted resources anywhere on the network using a single logon process. It provides network administrators with an intuitive, hierarchical view of the network and a single point of administration for all network objects.

See also: directory partition; service

Active Directory Users and Computers

An administrative tool designed to perform day-to-day Active Directory administration tasks. These tasks include creating, deleting, modifying, moving, and setting permissions on objects stored in the directory. These objects include organizational units, users, contacts, groups, computers, printers, and shared file objects.

See also: permission; Active Directory; object

active partition

A partition from which an x86-based computer starts up. The active partition must be a primary partition on a basic disk. If you use Windows exclusively, the active partition can be the same as the system volume.

See also: basic disk; primary partition; system partition; system volume; x86

active volume

The volume from which the computer starts up. The active volume must be a simple volume on a dynamic disk. You cannot mark an existing dynamic volume as the active volume, but you can upgrade a basic disk containing the active partition to a dynamic disk. Once the disk is upgraded to dynamic, the partition becomes a simple volume that is active.

See also: active partition; basic disk; dynamic disk; dynamic volume; simple volume


A set of technologies that allows software components to interact with one another in a networked environment, regardless of the language in which the components were created.


For Windows XP Professional, a person responsible for setting up and managing domain controllers or local computers and their user and group accounts, assigning passwords and permissions, and helping users with networking problems. Administrators are members of the Administrators group and have full control over the domain or computer.

For Windows XP Home Edition, a person who can make system-wide changes to the computer, install software, and who has access to all files on the computer. A person with a computer administrator account has full access to other user accounts on the computer.

Advanced Configuration and Power Interface (ACPI)

An open industry specification that defines power management on a wide range of mobile, desktop, and server computers and peripherals. ACPI is the foundation for the OnNow industry initiative that allows system manufacturers to deliver computers that will start at the touch of a keyboard. ACPI design is essential to take full advantage of power management and Plug and Play.

See also: Plug and Play

Advanced Program-to-Program Communication File Transfer Protocol (AFTP)

A file transfer protocol used in IBM host systems, the IBM Advanced Program-to-Program Communications equivalent to the TCP/IP File Transfer Protocol.

allocation unit

The smallest amount of disk space that can be allocated to hold a file. All file systems used by Windows organize hard disks based on allocation units. The smaller the allocation unit size, the more efficiently a disk stores information. If you do not specify an allocation unit size when formatting the disk, Windows picks default sizes based on the size of the volume. These default sizes are selected to reduce the amount of space that is lost and the amount of fragmentation on the volume. An allocation unit is also called a cluster.

See also: file system; volume

American Standard Code for Information Interchange (ASCII)

A standard single-byte character encoding scheme used for text-based data. ASCII uses designated 7-bit or 8-bit number combinations to represent either 128 or 256 possible characters. Standard ASCII uses 7 bits to represent all uppercase and lowercase letters, the numbers 0 through 9, punctuation marks, and special control characters used in U.S. English. Most current x86-based systems support the use of extended (or "high") ASCII. Extended ASCII allows the eighth bit of each character to identify an additional 128 special symbol characters, foreign-language letters, and graphic symbols.

See also: Unicode


The Apple Computer network architecture and network protocols. A network that has Macintosh clients and a computer running Windows 2000 Server or Windows NT Server with Services for Macintosh functions as an AppleTalk network.

ASCII (American Standard Code for Information Interchange)


For files, information that indicates whether a file is read-only, hidden, ready for archiving (backing up), compressed, or encrypted, and whether the file contents should be indexed for fast file searching.

In Active Directory, characteristics of an object and the type of information an object can hold. For each object class, the schema defines what attributes an instance of the class must have and what additional attributes it might have.

audio input device

An audio input device records music and voice input into your computer. Examples of audio input devices are CD-ROM players and microphones.


The process for verifying that an entity or object is who or what it claims to be. Examples include confirming the source and integrity of information, such as verifying a digital signature or verifying the identity of a user or computer.

See also: smart card; trust relationship


The process that determines what a user is permitted to do on a computer system or network.



The screen background image used on a graphical user interface such as Windows. Any pattern or picture that can be stored as a bitmap (.bmp) file can be set as a screen background.


In analog communications, the difference between the highest and lowest frequencies in a given range. For example, an analog telephone line accommodates a bandwidth of 3,000 hertz (Hz), the difference between the lowest (300 Hz) and highest (3,300 Hz) frequencies it can carry. In digital communications, bandwidth is expressed in bits per second (bps).

See also: bits per second (bps)

basic disk

A physical disk that can be accessed by MS-DOS and all Windows-based operating systems. Basic disks can contain up to four primary partitions, or three primary partitions and an extended partition with multiple logical drives. If you want to create partitions that span multiple disks, you must first convert the basic disk to a dynamic disk using Disk Management or the Diskpart.exe command-line utility.

See also: dynamic disk; extended partition; logical drive; MS-DOS (Microsoft Disk Operating System); primary partition

basic input/output system (BIOS)

On x86-based computers, the set of essential software routines that test hardware at startup, start the operating system, and support the transfer of data among hardware devices. The BIOS is stored in read-only memory (ROM) so that it can be executed when you turn on the computer. Although critical to performance, the BIOS is usually invisible to computer users.

See also: Extensible Firmware Interface (EFI); x86

basic storage

A storage method in MS-DOS, Windows, Windows NT, and Windows 2000 for primary partitions, extended partitions, and logical drives.

See also: dynamic storage; extended partition; logical drive

basic volume

A primary partition or logical drive that resides on a basic disk.

See also: basic disk; logical drive; primary partition

batch program

An ASCII (unformatted text) file that contains one or more operating system commands. A batch program's file name has a .cmd or .bat extension. When you type the file name at the command prompt, or when the batch program is run from another program, its commands are processed sequentially. Batch programs are also called batch files.

See also: American Standard Code for Information Interchange (ASCII); logon script

baud rate

The speed at which a modem communicates. Baud rate refers to the number of times the condition of the line changes. This is equal to bits per second only if each signal corresponds to one bit of transmitted data.

Modems must operate at the same baud rate in order to communicate with each other. If the baud rate of one modem is set higher than that of the other, the faster modem usually alters its baud rate to match that of the slower modem.

See also: bits per second (bps); modem (modulator/demodulator)


A base-2 number system in which values are expressed as combinations of two digits, 0 and 1.


bit (binary digit)

The smallest unit of information handled by a computer. One bit expresses a 1 or a 0 in a binary numeral, or a true or false logical condition. A group of 8 bits makes up a byte, which can represent many types of information, such as a letter of the alphabet, a decimal digit, or other character. Bit is also called binary digit.

See also: binary

bits per second (bps)

The number of bits transmitted every second, used as a measure of the speed at which a device, such as a modem, can transfer data.

See also: modem (modulator/demodulator)

BNC connector

A connector for coaxial cables that locks when one connector is inserted into another and rotated 90 degrees.


The process of starting or resetting a computer. When first turned on (cold boot) or reset (warm boot), the computer runs the software that loads and starts the computer's operating system, which prepares it for use.

boot partition

The partition that contains the Windows operating system and its support files. The boot partition can be, but does not have to be, the same as the system partition.

See also: partition; Primary disk; system partition

boot volume

The volume that contains the Windows operating system and its support files. The boot volume can be, but does not have to be, the same as the system volume.

See also: system volume; volume

broadband connection

A high-speed connection. Broadband connections are typically 256 kilobytes per second (KBps) or faster. Broadband includes DSL and cable modem service.


An address that is destined for all hosts on a particular network segment.


Software that interprets the markup of files in HTML, formats them into Web pages, and displays them to the end user. Some browsers also permit end users to send and receive e-mail, read newsgroups, and play sound or video files embedded in Web documents.

See also: World Wide Web


A region of RAM reserved for use with data that is temporarily held while waiting to be transferred between two locations, such as between an application's data area and an input/output device.

See also: random access memory (RAM)


A communication line used for data transfer among the components of a computer system. A bus essentially allows different parts of the system to share data. For example, a bus connects the disk-drive controller, memory, and input/output ports to the microprocessor.

See also: universal serial bus (USB)


A unit of data that typically holds a single character, such as a letter, a digit, or a punctuation mark. Some single characters can take up more than one byte.

See also: bit (binary digit); megabyte (MB)


cable modem

A device that enables a broadband connection to the Internet by using cable television infrastructure. Access speeds vary greatly, with a maximum throughput of 10 megabits per second (Mbps).

called subscriber ID (CSID) string

A string that specifies the called subscriber ID transmitted by the receiving fax machine when receiving an inbound fax. This string is usually a combination of the fax or telephone number and the name of the business. It is often the same as the transmitter subscriber ID.

See also: transmitting station ID (TSID) string


To assign a port to a printer. Documents that you print are sent to the printer through the captured port.

For Network Monitor, the process by which frames are copied.

cartridge font

A font contained in a plug-in cartridge and used to add fonts to laser, ink-jet, or high-end dot-matrix printers. Cartridge fonts are distinguished both from internal fonts, which are contained in ROM in the printer and are always available, and from downloadable (soft) fonts, which reside on disk and which can be sent to the printer as needed.

See also: downloadable fonts; font; font cartridge

cascading hubs

A network configuration in which hubs are connected to other hubs.

See also: hub


Recordable compact disc. Data can be copied to the CD on more than one occasion; however, data cannot be erased from the CD.


Rewritable compact disc. Data can be copied to the CD on more than one occasion and can be erased.


A digital document that is commonly used for authentication and secure exchange of information on open networks, such as the Internet, extranets, and intranets. A certificate securely binds a public key to the entity that holds the corresponding private key. Certificates are digitally signed by the issuing certification authority and can be issued for a user, a computer, or a service. The most widely accepted format for certificates is defined by the ITU-T X.509 version 3 international standard.

See also: service; certification authority (CA); private key

certificate revocation list (CRL)

A document maintained and published by a certification authority that lists certificates that have been revoked.

See also: certificate; certification authority (CA)

certificate store

Typically, a permanent storage where certificates, certificate revocation lists, and certificate trust lists are stored.

See also: certificate; certificate revocation list (CRL)

certification authority (CA)

An entity responsible for establishing and vouching for the authenticity of public keys belonging to users (end entities) or other certification authorities. Activities of a certification authority can include binding public keys to distinguished names through signed certificates, managing certificate serial numbers, and certificate revocation.

See also: certificate; root authority

certification hierarchy

A model of trust for certificates in which certification paths are created by means of the establishment of parent-child relationships between certification authorities.

See also: certification authority (CA)


A path or link through which noncontrol information passes between two devices. A single Basic Rate Interface (BRI) connection, for example, has one physical connection but two channels for exchanging information between devices. This is often called a bearer channel, implying a channel that carries information.

On the Internet, a Web site designed to deliver content from the Internet to your computer, similar to subscribing to a favorite Web site.

See also: active content

character mode

A display mode in which the monitor can display letters, numbers, and other text characters, but no graphical images or character formatting (italics, superscript, and so on).


See definition for: Restore Point

Class A IP address

A unicast IP address that ranges from through The first octet indicates the network, and the last three octets indicate the host on the network.

See also: Class B IP address; Class C IP address; IP address

Class B IP address

A unicast IP address that ranges from through The first two octets indicate the network, and the last two octets indicate the host on the network.

See also: Class A IP address; Class C IP address; IP address

Class C IP address

A unicast IP address that ranges from to The first three octets indicate the network, and the last octet indicates the host on the network. Network Load Balancing provides optional session support for Class C IP addresses (in addition to support for single IP addresses) to accommodate clients that make use of multiple proxy servers at the client site.

See also: Class A IP address; Class B IP address; IP address


To turn off an option by removing the X or check mark from a check box. You clear a check box by clicking it, or by selecting it and then pressing the SPACEBAR.


To position the mouse over an object, and then press and release the primary (left) mouse button.


Any computer or program connecting to, or requesting the services of, another computer or program. Client can also refer to the software that enables the computer or program to establish the connection.

For a local area network (LAN) or the Internet, a computer that uses shared network resources provided by another computer (called a server).

See also: server

color depth

The number of colors per pixel your monitor and graphics adapter support.

color gamut

The particular range of colors that a device is able to produce. A device such as a scanner, monitor, or printer can produce a unique range of colors, which is determined by the characteristics of the device itself.

See also: color profile; rendering intent

color profile

A profile that contains the data needed for translating the values of a color gamut. This data includes information about color, hue, saturation, and brightness.

See also: color gamut; hue; saturation

command prompt window

A window displayed on the desktop used to interface with the MS-DOS operating system. MS-DOS commands are typed at an entry point identified by a blinking cursor.

See also: MS-DOS (Microsoft Disk Operating System)

common groups

Groups that appear in the program list on the Start menu for all users who log on to the computer. Only administrators can create or change common groups.

See also: group

communication port

A port on a computer that allows asynchronous communication of one byte at a time. A communication port is also called a serial port.

See also: serial port

communication settings

Operating parameters, such as bits per second (bps) and modem type, that apply to serial ports on a computer.

See also: bits per second (bps); modem (modulator/demodulator); serial port

compatibility mode

A feature of a computer or operating system that allows it to run programs written for a different system. Programs often run slower in compatibility mode.

Complementary Metal Oxide Semiconductor (CMOS)

A specific type of semiconductor technology that requires very little power. The term has been popularized to mean a small storage area where your system keeps track of certain hardware parameters, such as the size of your hard disk, the number of serial ports your computer has, etc. CMOS is also called Setup RAM.

computer administrator

A user who manages a computer. The computer administrator makes system-wide changes to the computer, including installing programs and accessing all files on the computer, and can create, change and delete the accounts of other users.

connected, user authenticated

A user's status when a telephone connection has been established and the user has entered a correct user name and password. If the user has callback permission and has requested callback, the connection is followed by the calling-back phase. If the calling-back phase is followed by a waiting-for-call phase, then the server was unable to reach the user at the specified number. The user may have supplied an inaccurate callback number (in the case of set-by-caller callback), or an unauthorized attempt to access the network may be under way (in the case of preset-to callback).

See also: preset-to callback; set-by-caller callback

console tree

The left pane in a Microsoft Management Console (MMC) that displays the items contained in the console. By default it is the left pane of a console window, but it can be hidden. The items in the console tree and their hierarchical organization determine the capabilities of a console.


default user

The profile that serves as a basis for all user profiles. Every user profile begins as a copy of the default user profile.


The process of rewriting parts of a file to contiguous sectors on a hard disk to increase the speed of access and retrieval. When files are updated, the computer tends to save these updates on the largest continuous space on the hard disk, which is often on a different sector than the other parts of the file. When files are thus fragmented, the computer must search the hard disk each time the file is opened to find all of the file's parts, which slows down response time.

See also: fragmentation


The on-screen work area on which windows, icons, menus, and dialog boxes appear.

desktop pattern

A design that appears across your desktop. You can create your own pattern or select a pattern provided by Windows.

See also: desktop

destination document

The document into which a package or a linked or embedded object is being inserted. For an embedded object, this is sometimes also called the container document.

See also: embedded object


Any piece of equipment that can be attached to a network or computer; for example, a computer, printer, joystick, adapter, or modem card, or any other peripheral equipment. Devices normally require a device driver to function with Windows.

See also: device driver; peripheral

device driver

A program that allows a specific device, such as a modem, network adapter, or printer, to communicate with the operating system. Although a device might be installed on your system, Windows cannot use the device until you have installed and configured the appropriate driver.

If a device is listed in the Hardware Compatibility List (HCL), a driver is usually included with Windows. Device drivers load automatically (for all enabled devices) when a computer is started, and thereafter run invisibly.

device fonts

Fonts that reside in your printer. They can be built into the printer itself or provided by a font cartridge or font card.

See also: font; font cartridge; printer fonts

Device Manager

An administrative tool that you can use to manage the devices on your computer. Using Device Manager, you can view and change device properties, update device drivers, configure device settings, and uninstall devices.

See also: device; uninstall

dial-up connection

The connection to your network if you are using a device that uses the telephone network. This includes modems with a standard phone line, ISDN cards with high-speed ISDN lines, or X.25 networks.

If you are a typical user, you may have one or two dial-up connections, for example, to the Internet and to your corporate network. In a more complex server situation, multiple network modem connections might be used to implement advanced routing.

See also: Integrated Services Digital Network (ISDN); modem (modulator/demodulator)

dialog box

A secondary window that contains buttons and various kinds of options through which you can carry out a particular command or task.

dictionary attack

A method of guessing a user's password or PIN by trying every word in the dictionary until successful.

digital signature

A means for originators of a message, file, or other digitally encoded information to bind their identity to the information. The process of digitally signing information entails transforming the information, as well as some secret information held by the sender, into a tag called a signature. Digital signatures are used in public key environments, and they provide nonrepudiation and integrity services.

See also: service; time stamp

Digital Subscriber Line (DSL)

A type of high-speed Internet connection using standard telephone wires. This is also referred to as a broadband connection.

digital video disc (DVD)

A type of optical disc storage technology. A digital video disc (DVD) looks like a CD-ROM disc, but it can store greater amounts of data. DVDs are often used to store full-length movies and other multimedia content that requires large amounts of storage space.

direct cable connection

A link between the I/O ports of two computers created with a single cable rather than a modem or other interfacing devices. In most cases, a direct cable connection is made with a null modem cable.

See also: input/output (I/O) port; null modem cable

directory partition

A contiguous subtree of the directory that forms a unit of replication. A given replica is always a replica of some directory partition. The directory always has at least three directory partitions:

  • The schema, which defines the object classes and attributes contained in Active Directory.
  • The configuration, which identifies the domain controllers, replication topology and other related information about the domain controllers within a specific implementation of Active Directory.
  • One or more domains that contain the actual directory object data.

A domain controller always stores the partitions for the schema, configuration, and its own (and no other) domain. The schema and configuration are replicated to every domain controller in the domain tree or forest. The domain is replicated only to domain controllers for that domain. A subset of the attributes for all domain objects is replicated to the global catalog.

See also: Active Directory; attribute; domain; replica; replication


An extension of the Microsoft Windows operating system. DirectX technology helps games and other programs use the advanced multimedia capabilites of your hardware.


A storage device that is attached to a computer.

See also: basic disk; dynamic disk


To remove a removable tape or disc from a drive.

See also: library; mount

display adapter

See definition for: video adapter


See definition for: dynamic-link library (DLL)


See definition for: Domain Name System (DNS)


To connect a laptop or notebook computer to a docking station.

See also: undock; docking station; hot docking

docking station

A unit for housing a portable computer that contains a power connection, expansion slots, and connections to peripherals, such as a monitor, printer, full-sized keyboard, and mouse. The docking station turns the portable computer into a desktop computer.

See also: dock; hot docking; undock


A group of computers that are part of a network and share a common directory database. A domain is administered as a unit with common rules and procedures. Each domain has a unique name.

An Active Directory domain is a collection of computers defined by the administrator of a Windows network. These computers share a common directory database, security policies, and security relationships with other domains. An Active Directory domain provides access to the centralized user accounts and group accounts maintained by the domain administrator. An Active Directory forest is made up of one or more domains, each of which can span more than one physical location.

A DNS domain is any tree or subtree within the DNS namespace. Although the names for DNS domains often correspond to Active Directory domains, DNS domains should not be confused with Active Directory domains.

See also: Active Directory; Domain Name System (DNS)

domain local group

A security or distribution group that can contain universal groups, global groups, and accounts from any domain in the domain tree or forest. A domain local group can also contain other domain local groups from its own domain. Rights and permissions can be assigned only at the domain containing the group.

See also: domain tree; global group; security group; universal group

domain name

The name given by an administrator to a collection of networked computers that share a common directory. Part of the Domain Name System (DNS) naming structure, domain names consist of a sequence of name labels separated by periods.

See also: domain; Domain Name System (DNS); label; namespace

Domain Name System (DNS)

A hierarchical, distributed database that contains mappings of DNS domain names to various types of data, such as IP addresses. DNS enables the location of computers and services by user-friendly names, and it also enables the discovery of other information stored in the database.

See also: domain; service; Transmission Control Protocol/Internet Protocol (TCP/IP); IP address

domain namespace

The database structure used by the Domain Name System (DNS).

See also: Domain Name System (DNS)

domain tree

In DNS, the inverted hierarchical tree structure that is used to index domain names. Domain trees are similar in purpose and concept to the directory trees used by computer filing systems for disk storage.

For example, when numerous files are stored on disk, directories can be used to organize the files into logical collections. When a domain tree has one or more branches, each branch can organize domain names used in the namespace into logical collections.

In Active Directory, a hierarchical structure of one or more domains, connected by transitive, bidirectional trusts, that forms a contiguous namespace. Multiple domain trees may belong to the same forest.

See also: Active Directory; domain; domain name; Domain Name System (DNS); namespace

double-byte characters

A set of characters in which each character is represented by two bytes. Some languages, such as Japanese, Chinese, and Korean, require double-byte character sets.


To transfer a copy of a file from a remote computer to the requesting computer by means of a modem or network.

downloadable fonts

A set of characters stored on disk and sent (downloaded) to a printer's memory when needed for printing a document. Downloadable fonts are most commonly used with laser printers and other page printers, although many dot-matrix printers can accept some of them. Downloadable fonts are also called soft fonts.

See also: font; font cartridge; PostScript fonts


To move an item on the screen by selecting the item and then pressing and holding down the mouse button while moving the mouse. For example, you can move a window to another location on the screen by dragging its title bar.


An area of storage that is formatted with a file system and has a drive letter. The storage can be a floppy disk, a CD, a hard disk, or another type of disk. You can view the contents of a drive by clicking its icon in Windows Explorer or My Computer.

See also: drive letter; file system; volume

drive letter

The naming convention for disk drives on IBM and compatible computers. Drives are named by letter, beginning with A, followed by a colon.

See also: drive

dual boot

A computer configuration that can start two different operating systems.

See also: boot; multiple boot; startup environment

dynamic disk

A physical disk that can be accessed only by Windows 2000 and Windows XP. Dynamic disks provide features that basic disks do not, such as support for volumes that span multiple disks. Dynamic disks use a hidden database to track information about dynamic volumes on the disk and other dynamic disks in the computer. You convert basic disks to dynamic by using the Disk Management snap-in or the DiskPart command line utility. When you convert a basic disk to dynamic, all existing basic volumes become dynamic volumes.

See also: active volume; basic disk; basic volume; dynamic volume; volume

Dynamic Host Configuration Protocol (DHCP)

A TCP/IP service protocol that offers dynamic leased configuration of host IP addresses and distributes other configuration parameters to eligible network clients. DHCP provides safe, reliable, and simple TCP/IP network configuration, prevents address conflicts, and helps conserve the use of client IP addresses on the network.

DHCP uses a client/server model where the DHCP server maintains centralized management of IP addresses that are used on the network. DHCP-supporting clients can then request and obtain lease of an IP address from a DHCP server as part of their network boot process.

See also: service; Transmission Control Protocol/Internet Protocol (TCP/IP); IP address

dynamic storage

A storage method in Windows that allows disk and volume management without requiring operating system restart.

See also: basic storage

dynamic volume

A volume that resides on a dynamic disk. Windows supports five types of dynamic volumes: simple, spanned, striped, mirrored, and RAID-5. A dynamic volume is formatted by using a file system, such as FAT or NTFS, and it has a drive letter assigned to it.

See also: basic disk; basic volume; dynamic disk; mirrored volume; RAID-5 volume; simple volume; spanned volume; volume

dynamic-link library (DLL)

An operating system feature that allows executable routines (generally serving a specific function or set of functions) to be stored separately as files with .dll extensions. These routines are loaded only when needed by the program that calls them.

See also: Resource DLL



EFI system partition

On Itanium-based computers, a portion on a GUID partition table (GPT) disk that is formatted with the FAT file system and contains the files necessary to start the computer. Every Itanium-based computer must have at least one GPT disk with an EFI system partition. The EFI system partition serves the same purpose as the system volume found on x86-based computers.

See also: Extensible Firmware Interface (EFI); Microsoft Reserved (MSR) partition; x86

embedded object

Information created in another program that has been pasted inside your document. When information is embedded, you can edit the information in the new document using toolbars and menus from the original program.

To edit the embedded information, double-click it and the toolbars and menus from the program used to create the information appear. Embedded information is not linked to the original source. If you change information in one place, it is not updated in the other.

See also: package; source document; OLE

Encrypting File System (EFS)

A feature in this version of Windows that enables users to encrypt files and folders on an NTFS volume disk to keep them safe from access by intruders.

See also: recovery agent; NTFS file system


The process of disguising a message or data in such a way as to hide its substance.

See also: symmetric encryption

expanded memory

Type of memory that can be added to IBM personal computers. The use of expanded memory is defined by the Expanded Memory Specification (EMS), which supports memory boards containing RAM that can be enabled or disabled by software.

See also: extended memory

extended characters

Any of the 128 additional characters in the extended ASCII (8-bit) character set. These characters include those in several non-English languages, such as accent marks, and special symbols used for creating pictures.

extended memory

Memory beyond one megabyte in 80286, 80386, 80486, and Pentium computers.

See also: expanded memory

extended partition

A type of partition that you can create only on basic master boot record (MBR) disks. Extended partitions are useful if you want to create more than four volumes on a basic MBR disk. Unlike primary partitions, you do not format an extended partition with a file system and then assign a drive letter to it. Instead, you create one or more logical drives within the extended partition. After you create a logical drive, you format it and assign it a drive letter. An MBR disk can have up to four primary partitions, or three primary partitions, one extended partition, and multiple logical drives.

See also: basic disk; drive letter; logical drive; master boot record (MBR); partition; primary partition; volume

Extensible Firmware Interface (EFI)

In computers with the Intel Itanium processor, the interface between a computer's firmware, hardware, and the operating system. The Extensible Firmware Interface (EFI) defines a new partition style called GUID partition table (GPT). EFI serves the same purpose for Itanium-based computers as the BIOS found in x86-based computers. However, it has expanded capabilities that provide a consistent way to start any compatible operating system and an easy way to add EFI drivers for new bootable devices without the need to update the computer's firmware.

See also: x86; basic input/output system (BIOS)

Extensible Markup Language (XML)

A meta-markup language that provides a format for describing structured data. This facilitates more precise declarations of content and more meaningful search results across multiple platforms. In addition, XML will enable a new generation of Web-based data viewing and manipulation applications.


When you extract a file, an uncompressed copy of the file that is created in a folder you specify. The original file remains in the compressed folder.



See definition for: file allocation table (FAT)


A derivative of the file allocation table (FAT) file system. FAT32 supports smaller cluster sizes and larger volumes than FAT, which results in more efficient space allocation on FAT32 volumes.

See also: file allocation table (FAT); NTFS file system; volume

Fax Service

A system service that provides fax services to local and remote network clients. Fax services include receiving faxes and faxing documents, fax wizard messages, and e-mail messages.

See also: service


A complete, named collection of information, such as a program, a set of data used by a program, or a user-created document. A file is the basic unit of storage that enables a computer to distinguish one set of information from another. It is a collection of data that a user can retrieve, change, delete, save, or send to an output device, such as a printer or e-mail program.

file allocation table (FAT)

A file system used by MS-DOS and other Windows-based operating systems to organize and manage files. The file allocation table (FAT) is a data structure that Windows creates when you format a volume by using the FAT or FAT32 file systems. Windows stores information about each file in the FAT so that it can retrieve the file later.

See also: FAT32; file system; NTFS file system

file name extension

File name extensions follow the period in a file name and indicate the type of information stored in a file. For example, in the file name Example.txt, the file name extension is .txt, which indicates that the file is a text file.

file system

In an operating system, the overall structure in which files are named, stored, and organized. NTFS, FAT, and FAT32 are types of file systems.

See also: FAT; FAT32; NTFS file system

File Transfer Protocol (FTP)

A member of the TCP/IP suite of protocols, used to copy files between two computers on the Internet. Both computers must support their respective FTP roles: one must be an FTP client and the other an FTP server.

See also: Transmission Control Protocol/Internet Protocol (TCP/IP)

file type

In the Windows environment, a designation of the operational or structural characteristics of a file. The file type identifies the program, such as Microsoft Word, that is used to open the file. File types are associated with a file name extension. For example, files that have the .txt or .log extension are of the Text Document type and can be opened using any text editor.

In the Macintosh environment, a four-character sequence that identifies the type of a Macintosh file. The Macintosh Finder uses the file type and file creator to determine the appropriate desktop icon for that file.


A keyboard feature that instructs your keyboard to ignore brief or repeated keystrokes. You can also adjust the keyboard repeat rate, which is the rate at which a key repeats when you hold it down.

See also: StickyKeys; ToggleKeys; MouseKeys


A combination of hardware and software that provides a security system, usually to prevent unauthorized access from outside to an internal network or intranet. A firewall prevents direct communication between network and external computers by routing communication through a proxy server outside of the network. The proxy server determines whether it is safe to let a file pass through to the network. A firewall is also called a security-edge gateway.

floppy disk

A reusable magnetic storage medium. The floppy disk used today is the rigid 3.5-inch microfloppy that holds 1.44 MB. It is called a floppy because the first varieties were housed in bendable jackets.


A container for programs and files in graphical user interfaces, symbolized on the screen by a graphical image (icon) of a file folder. A folder is a means of organizing programs and documents on a disk and can hold both files and additional folders.


A graphic design applied to a collection of numbers, symbols, and characters. A font describes a certain typeface, along with other qualities such as size, spacing, and pitch.

See also: OpenType fonts; PostScript fonts; screen fonts; Type 1 fonts

font cartridge

A plug-in unit available for some printers that contains fonts in several styles and sizes. As with downloadable fonts, printers using font cartridges can produce characters in sizes and styles other than those created by the fonts built into it.

See also: downloadable fonts; font


The scattering of parts of the same disk file over different areas of the disk. Fragmentation occurs as files on a disk are deleted and new files are added. It slows disk access and degrades the overall performance of disk operations, although usually not severely.

See also: defragmentation

FTP (File Transfer Protocol)

See definition for: File Transfer Protocol (FTP)

full name

A user's complete name, usually consisting of the last name, first name, and middle initial. The full name is information that Local Users and Groups or Active Directory Users and Computers can maintain as part of the information identifying and defining a user account.

See also: Active Directory Users and Computers; user account


game port

An input/output connector to which you attach a joy stick or other game device to your computer. It is typically a 15-pin socket on the back of a PC.

See also: serial port


A device connected to multiple physical TCP/IP networks capable of routing or delivering IP packets between them. A gateway translates between different transport protocols or data formats (for example, IPX and IP) and is generally added to a network primarily for its translation ability.

In the context of interoperating with Novell NetWare networks, a gateway acts as a bridge between the server message block (SMB) protocol used by Windows networks and the NetWare core protocol (NCP) used by NetWare networks. A gateway is also called an IP router.

gigabyte (GB)

1,024 megabytes, though often interpreted as approximately one billion bytes.

See also: kilobyte (KB); megabyte (MB)

global group

A security or distribution group that can have users, groups, and computers from its own domain as members. Global security groups can be granted rights and permissions on resources in any domain in the forest. Global groups cannot be created or maintained on computers running Windows XP Professional. However, for Windows XP Professional computers that participate in a domain, domain global groups can be granted rights and permissions at those workstations and can become members of local groups at those workstations.

See also: permission; group; local group; user account


A collection of users, computers, contacts, and other groups. Groups can be used as security or as e-mail distribution collections. Distribution groups are used only for e-mail. Security groups are used both to grant access to resources and as e-mail distribution lists.

See also: domain; global group; local group

group account

A collection of user accounts. By making a user account a member of a group, you give the related user all the rights and permissions granted to the group.

See also: group; user account

group memberships

The groups to which a user account belongs. Permissions and rights granted to a group are also provided to its members. In most cases, the actions a user can perform in Windows are determined by the group memberships of the user account to which the user is logged on.

See also: group; user account

group name

A unique name identifying a local group or a global group to Windows. A group's name cannot be identical to any other group name or user name in its own domain or computer.

See also: global group; local group

Group Policy

The Microsoft Management Console (MMC) snap-in that is used to edit Group Policy objects.

See also: Group Policy object; policy; snap-in

Group Policy object

A collection of Group Policy settings. Group Policy objects are essentially the documents created by the Group Policy snap-in, a Windows utility. Group Policy objects are stored at the domain level, and they affect users and computers contained in sites, domains, and organizational units. In addition, each Windows computer has exactly one group of settings stored locally, called the local Group Policy object.

See also: Group Policy; object; policy


handwriting input device

A tool, such as a digital pen and tablet, used to enter text by writing instead of typing. Along with writing tablets, you can use 3-D drawing or Computer Aided Drafting (CAD) tablets, or a tablet-PC. You can also write by moving your mouse on the mouse pad.

hard disk

A device, also called hard disk drive, that contains one or more inflexible platters coated with material in which data can be recorded magnetically with read/write heads. The hard disk exists in a sealed case that protects it and allows the head to fly 10 millionths to 25 millionths of an inch above the surface of a platter. Data can both be stored and accessed much more quickly than on a floppy disk.


The physical components of a computer system, including any peripheral equipment such as printers, modems, and mouse devices.

hardware compression

A feature available on some tape devices that automatically compresses the data that is being stored on the device. This is usually an option that is turned on or off in a backup program.

hardware configuration

Resource settings that have been allocated for a specific device. Each device on your computer has a hardware configuration, which may consist of IRQ lines, DMA, an I/O port, or memory address settings.

See also: device; input/output (I/O) port; memory address

hardware profile

Data that describes the configuration and characteristics of specific computer equipment. This information can be used to configure computers for using peripheral devices.

See also: device

hardware type

A classification for similar devices. For example, Imaging Device is a hardware type for digital cameras and scanners.

See also: device


A state in which your computer shuts down after saving everything in memory on your hard disk. When you bring your computer out of hibernation, all programs and documents that were open are restored to your desktop.

See also: standby

High Contrast

A display feature that instructs programs to change the color scheme to a high-contrast scheme and to increase legibility whenever possible.


A section of the registry that appears as a file on your hard disk. The registry subtree is divided into hives (named for their resemblance to the cellular structure of a beehive). A hive is a discrete body of keys, subkeys, and values that is rooted at the top of the registry hierarchy. A hive is backed by a single file and a .log file, which are in the systemroot\System32\Config or the systemroot\Profiles\username folders.

By default, most hive files (Default, SAM, Security, and System) are stored in the systemroot\System32\Config folder. The systemroot\Profiles folder contains the user profile for each user of the computer. Because a hive is a file, it can be moved from one system to another. However, you must use the Registry Editor to edit the file.

See also: registry; key; systemroot

home folder

A folder (usually on a file server) that administrators can assign to individual users or groups. Administrators use home folders to consolidate user files onto specific file servers for easy backup. Home folders are used by some programs as the default folder for the Open and Save As dialog boxes. Home folders are sometimes referred to as home directories.

See also: administrator; group


A Windows computer that runs a server program or service used by network or remote clients. For Network Load Balancing, a cluster consists of multiple hosts connected over a local area network (LAN).

See also: client; local area network (LAN); server; service

host name

The DNS name of a device on a network. These names are used to locate computers on the network. To find another computer, its host name must either appear in the Hosts file or be known by a DNS server. For most Windows computers, the host name and the computer name are the same.

See also: Domain Name System (DNS)

host priority

For Network Load Balancing, a host's precedence for handling default network traffic for TCP and UDP ports. It is used if a host within the cluster goes offline, and it determines which host within the cluster will assume responsibility for the traffic previously handled by the offline host.

See also: host

hot docking

The process of attaching a laptop computer to a docking station while the computer is running, and automatically activating the docking station's video display and other functions.

See also: dock; docking station; undock



A common connection point for devices in a network. Typically used to connect segments of a local area network (LAN), a hub contains multiple ports. When data arrives at one port, it is copied to the other ports so that all segments of the LAN can see the data.

See also: switching hub; local area network (LAN); port

hubbed mode

A mode in which the ARP/MARS provides ATM addresses to requesting clients in the form of a multicast server (MCS) list value. In this mode, the ARP/MARS acts as a multicast server, providing active forwarding of all multicast and broadcast traffic destined for IP addresses contained within the ranges specified in the list.

See also: IP address


The position of a color along the color spectrum. For example, green is between yellow and blue. This attribute can be set using Display in Control Panel.

See also: saturation


Colored and underlined text or a graphic that you click to go to a file, a location in a file, an HTML page on the World Wide Web, or an HTML page on an intranet. Hyperlinks can also go to newsgroups and to Gopher, Telnet, and FTP sites.

In Windows folders, hyperlinks are text links that appear in the folder's left pane. You can click these links to perform tasks, such as moving or copying a file, or to go to other places on your computer, such as the My Documents folder or Control Panel.

Hypertext Markup Language (HTML)

A simple markup language used to create hypertext documents that are portable from one platform to another. HTML files are simple ASCII text files with codes embedded (indicated by markup tags) to denote formatting and hypertext links.

See also: American Standard Code for Information Interchange (ASCII)

Hypertext Transfer Protocol (HTTP)

The protocol used to transfer information on the World Wide Web. An HTTP address (one kind of Uniform Resource Locator [URL]) takes the form:



A small image displayed on the screen to represent an object that can be manipulated by the user. Icons serve as visual mnemonics and allow the user to control certain computer actions without having to remember commands or type them at the keyboard.

IEEE 1394

A standard for high-speed serial devices such as digital video and digital audio editing equipment.

See also: device

IEEE 1394 connector

A type of connector that enables you to connect and disconnect high-speed serial devices. An IEEE 1394 connector is usually on the back of your computer near the serial port or the parallel port.

If a device is IEEE 1394 compatible, you can connect the device to the IEEE 1394 connector while the computer is running and Windows will detect the device and inform you when it is ready for use. Similarly, you can unplug the device while the computer is running, but you should use the Add Hardware Wizard to inform Windows that you are unplugging the device. Windows will then inform you when the device can be unplugged from the computer.

The IEEE 1394 bus is used primarily to connect high-end digital video and digital audio devices to your computer; however, some hard disks, printers, scanners, and DVD drives can also be connected to your computer using the IEEE 1394 connector.

IEEE 1394 port

Ports that support either a 6-pin plug whose size is 11 mm by 5.4 mm or a 4-pin plug whose size is 5.35 mm by 3.45 mm.

infrared (IR)

Light that is beyond red in the color spectrum. While the light is not visible to the human eye, infrared transmitters and receivers can send and receive infrared signals.

See also: Infrared Data Association (IrDA); infrared device; infrared port

Infrared Data Association (IrDA)

The industry organization of computer, component, and telecommunications vendors who establish the standards for infrared communication between computers and peripheral devices, such as printers.

See also: infrared (IR)

infrared device

A computer, or a computer peripheral such as a printer, that can communicate using infrared light.

See also: infrared (IR)

infrared file transfer

Wireless file transfer between a computer and another computer or device using infrared light.

See also: infrared (IR)

infrared port

An optical port on a computer that enables communication with other computers or devices by using infrared light, without cables. Infrared ports can be found on some portable computers, printers, and cameras.

See also: infrared (IR); infrared device; port

Initial master

A shared folder whose existing files and folders are replicated to other shared folders when replication is initially configured. After replication is complete, there is no initial master, since any of the replicas can accept changes and propagate them to the other replicas. The initial master then becomes another replica.

See also: shared folder; replica; replication


In Disk Management, the process of detecting a disk or volume and assigning it a status (for example, healthy) and a type (for example, dynamic).

See also: basic disk; basic volume; dynamic disk; dynamic volume


An option that allows you to enter text in handwritten form. Instead of converting your handwritten text to typed text, the text is converted to an object and displayed exactly as you wrote it. For example: hello.

input language

The specification of the language you want to type in. Some programs that are designed for Windows recognize this setting. When you add a new input language, a keyboard layout for that language is also added.

input/output (I/O) port

A channel through which data is transferred between a device and the microprocessor. The port appears to the microprocessor as one or more memory addresses that it can use to send or receive data.

See also: device; memory address; port

insertion point

The place where text will be inserted when typed. The insertion point usually appears as a flashing vertical bar in an application's window or in a dialog box.


When referring to software, to add program files and folders to your hard disk and related data to your registry so that the software runs properly. Installing contrasts with upgrading, where existing program files, folders, and registry entries are updated to a more recent version.

When referring to hardware, to physically connect the device to your computer, to load device drivers onto your computer, and to configure device properties and settings.

See also: device driver; registry; uninstall

integrated device electronics (IDE)

A type of disk-drive interface in which the controller electronics reside on the drive itself, eliminating the need for a separate adapter card. IDE offers advantages such as look-ahead caching to increase overall performance.

Integrated Services Digital Network (ISDN)

A digital phone line used to provide higher bandwidth. ISDN in North America is typically available in two forms: Basic Rate Interface (BRI) consists of 2 B-channels at 64 kilobits per second (Kbps) and a D-channel at 16 Kbps; Primary Rate Interface (PRI) consists of 23 B-channels at 64 Kbps and a D-channel at 64 Kbps. An ISDN line must be installed by the phone company at both the calling site and the called site.

See also: multilink dialing; Service Profile Identifier (SPID); switch type


A private network that connects nodes in a cluster.

internal network number

A 4-byte hexadecimal number used for addressing and routing purposes. The internal network number identifies a virtual network inside a computer. The internal network number must be unique to the IPX internetwork. Internal network number is also called virtual network number.


internet. Two or more network segments connected by routers. Another term for internetwork.

Internet. A worldwide network of computers. If you have access to the Internet, you can retrieve information from millions of sources, including schools, governments, businesses, and individuals.

See also: World Wide Web

Internet address

An address for a resource on the Internet that is used by Web browsers to locate Internet resources. An Internet address typically starts with a protocol name, followed by the name of the organization that maintains the site; the suffix identifies the kind of organization it is. For example, the address provides the following information:

  • http: This Web server uses the Hypertext Transfer Protocol.
  • www: This site is on the World Wide Web.
  • edu: This is an educational institution.
Internet address is also called Uniform Resource Locator (URL).

See also: Web server; protocol

Internet Engineering Task Force (IETF)

An open community of network designers, operators, vendors, and researchers concerned with the evolution of Internet architecture and the smooth operation of the Internet. Technical work is performed by working groups organized by topic areas (such as routing, transport, and security) and through mailing lists. Internet standards are developed in IETF Requests for Comments (RFCs), which are a series of notes that discuss many aspects of computing and computer communication, focusing on networking protocols, programs, and concepts.

Internet Group Management Protocol (IGMP)

A protocol used by IP hosts to report their multicast group memberships to any immediately neighboring multicast routers.

See also: protocol; Internet Protocol multicasting

Internet Information Services (IIS)

Software services that support Web site creation, configuration, and management, along with other Internet functions. Internet Information Services include Network News Transfer Protocol (NNTP), File Transfer Protocol (FTP), and Simple Mail Transfer Protocol (SMTP).

See also: File Transfer Protocol (FTP); Network News Transfer Protocol (NNTP)

Internet Protocol (IP)

A routable protocol in the TCP/IP protocol suite that is responsible for IP addressing, routing, and the fragmentation and reassembly of IP packets.

See also: packet; Transmission Control Protocol/Internet Protocol (TCP/IP)

Internet Protocol multicasting

The extension of local area network multicasting technology to a TCP/IP network. Hosts send and receive multicast datagrams, the destination fields of which specify IP host group addresses rather than individual IP addresses. A host indicates that it is a member of a group by means of the Internet Group Management Protocol (IGMP).

See also: Internet Group Management Protocol (IGMP); Transmission Control Protocol/Internet Protocol (TCP/IP)

Internet service provider (ISP)

A company that provides individuals or companies access to the Internet and the World Wide Web. An ISP provides a telephone number, a user name, a password, and other connection information so users can connect their computers to the ISP's computers. An ISP typically charges a monthly or hourly connection fee.

See also: Web server


A request for attention from the processor. When the processor receives an interrupt, it suspends its current operations, saves the status of its work, and transfers control to a special routine known as an interrupt handler, which contains the instructions for dealing with the particular situation that caused the interrupt.


A network within an organization that uses Internet technologies and protocols, but is available only to certain people, such as employees of a company. An intranet is also called a private network.

IP address

A 32-bit address used to identify a node on an IP internetwork. Each node on the IP internetwork must be assigned a unique IP address, which is made up of the network ID, plus a unique host ID. This address is typically represented with the decimal value of each octet separated by a period (for example, In this version of Windows, you can configure the IP address statically or dynamically through DHCP.

See also: Dynamic Host Configuration Protocol (DHCP)


Transport protocols used in Novell NetWare networks, which together correspond to the combination of TCP and IP in the TCP/IP protocol suite. Windows implements IPX through NWLink.

See also: Transmission Control Protocol/Internet Protocol (TCP/IP)

ISA expansion slot

A connection socket for a peripheral designed to the Industry Standard Architecture (ISA) on a computer motherboard.

ISDN (Integrated Services Digital Network)

A high-speed digital telephone service that can dramatically increase the speed at which you connect to the Internet or to your corporate LAN (local area network). ISDN can operate at 128 kilobytes per second (Kbps), which is five or more times faster than many analog modems.

ISP (Internet service provider)

See definition for: Internet service provider (ISP)


job object

A system-level structure that allows processes to be grouped together and managed as a single unit.



In Registry Editor, a folder that appears in the left pane of the Registry Editor window. A key can contain subkeys and value entries. For example, Environment is a key of HKEY_CURRENT_USER.

In IP security (IPSec), a value used in combination with an algorithm to encrypt or decrypt data. Key settings for IP security are configurable to provide greater security.

See also: registry; subkey

keyboard language

The language you want to use when you type. Some programs that are designed for the Windows platform recognize this setting. When you add a new keyboard language, a keyboard layout for that language is also added.

keyboard layout

The arrangement that accommodates the special characters and symbols used in different languages. Keyboard layouts affect which characters appear when you press the keys on your keyboard. After you change your keyboard layout, the characters that appear on your screen may no longer correspond to the characters that are printed on your keyboard keys.

kilobyte (KB)

1,024 bytes, though often interpreted as 1,000 bytes.

See also: gigabyte (GB); megabyte (MB)


L2TP (Layer 2 Tunneling Protocol)

An industry-standard Internet tunneling protocol. Unlike Point-to-Point Tunneling Protocol (PPTP), L2TP does not require IP connectivity between the client workstation and the server. L2TP requires only that the tunnel medium provide packet-oriented point-to-point connectivity. The protocol can be used over media such as ATM, Frame Relay, and X.25. L2TP provides the same functionality as PPTP. Based on Layer 2 Forwarding (L2F) and PPTP specifications, L2TP allows clients to set up tunnels across intervening networks.

See also: Internet Protocol (IP); Point-to-Point Tunneling Protocol (PPTP); tunnel


Each part of a full DNS domain name that represents a node in the domain namespace tree. Domain names are made up of a sequence of labels, such as the three labels (example, microsoft, and com) that make up the DNS domain name Each label used in a DNS name must be 63 bytes or less in character length.

See also: domain name; Domain Name System (DNS)

LAN emulation (LANE)

A set of protocols that allow existing Ethernet and Token Ring LAN services to overlie an ATM network. LANE allows connectivity among LAN- and ATM-attached stations.

See also: local area network (LAN); protocol

LAN emulation client (LEC)

The client on an ELAN that performs data forwarding, address resolution, and other control functions. The LEC resides on end stations in an ELAN.

See also: client; LAN emulation (LANE)

LAN emulation configuration server

The service that assigns individual local area network emulation (LANE) clients to particular emulated local area networks (ELANs) by directing them to the LAN emulation server (LES).

See also: LAN emulation (LANE); service

LCD (Liquid Crystal Display)

See definition for: liquid crystal display (LCD)


A data-storage system, usually managed by Removable Storage. A library consists of removable media (such as tapes or discs) and a hardware device that can read from or write to the media. There are two major types of libraries: robotic libraries (automated multiple-media, multidrive devices) and stand-alone drive libraries (manually operated, single-drive devices). A robotic library is also called a jukebox or changer.

See also: Removable Storage

Line Printer Daemon (LPD)

A service on the print server that receives documents (print jobs) from Line Printer Remote (LPR) utilities running on client systems.

See also: Line Printer Remote (LPR); print job; print server; service

Line Printer Remote (LPR)

A connectivity utility that runs on client systems and is used to print files to a computer running an LPD server.

See also: Line Printer Daemon (LPD)

linked object

An object that is inserted into a document but still exists in the source file. When information is linked, the new document is updated automatically if the information in the original document changes. If you want to edit the linked information, double-click it. The toolbars and menus from the original program will appear. If the original document is on your computer, changes that you make to the linked information will also appear in the original document.

See also: embedded object; OLE; package; source document

liquid crystal display (LCD)

A type of display used in digital watches and many portable computers. LCD displays utilize two sheets of polarizing material with a liquid crystal solution between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. Each crystal, therefore, is like a shutter, either allowing light to pass through or blocking the light.

load balancing

A technique used by Windows Clustering to scale the performance of a server-based program (such as a Web server) by distributing its client requests across multiple servers within the cluster. Each host can specify the load percentage that it will handle, or the load can be equally distributed across all the hosts. If a host fails, Windows Clustering dynamically redistributes the load among the remaining hosts.

See also: host

local area network (LAN)

A communications network connecting a group of computers, printers, and other devices located within a relatively limited area (for example, a building). A LAN allows any connected device to interact with any other on the network.

See also: NetBIOS Extended User Interface (NetBEUI); virtual local area network (VLAN); workgroup

local group

For computers running Windows and member servers, a group that can be granted permissions and rights from its own computer and (if the computer participates in a domain) user accounts and global groups both from its own domain and from trusted domains.

See also: global group; user account

log file

A file that stores messages generated by an application, service, or operating system. These messages are used to track the operations performed. For example, Web servers maintain log files listing every request made to the server. Log files are usually plain text (ASCII) files and often have a .log extension.

In Backup, a file that contains a record of the date the tapes were created and the names of files and directories successfully backed up and restored. The Performance Logs and Alerts service also creates log files.

See also: American Standard Code for Information Interchange (ASCII); service

logical drive

A volume that you create within an extended partition on a basic master boot record (MBR) disk. Logical drives are similar to primary partitions, except that you are limited to four primary partitions per disk, whereas you can create an unlimited number of logical drives per disk. A logical drive can be formatted and assigned a drive letter.

See also: basic disk; basic volume; drive letter; extended partition; master boot record (MBR); primary partition; volume

logical printer

The software interface between the operating system and the printer in Windows. While a printer is the device that does the actual printing, a logical printer is its software interface on the print server. This software interface determines how a print job is processed and how it is routed to its destination (to a local or network port, to a file, or to a remote print share). When you print a document, it is spooled (or stored) on the logical printer before it is sent to the printer itself.

See also: printer; spooling

logon script

Files that can be assigned to user accounts. Typically a batch file, a logon script runs automatically every time the user logs on. It can be used to configure a user's working environment at every logon, and it allows an administrator to influence a user's environment without managing all aspects of it. A logon script can be assigned to one or more user accounts.

See also: logon script path; user account

logon script path

A sequence of directory names that specifies the location of the logon script. When a user logs on, the authenticating computer locates the specified logon script (if one has been assigned to that user account) by following that computer's local logon script path (usually systemroot\System32\Repl\Import\Scripts).

See also: logon script; systemroot; user account

long name

A folder name or file name longer than the 8.3 file name standard (up to eight characters followed by a period and an extension of up to three characters) of the FAT file system. This version of Windows supports long file names up to 255 characters.

In a Macintosh environment, users can assign long names to files and folders on the server and, using AppleTalk network integration, you can assign long names to Macintosh-accessible volumes when you create them. This version of Windows automatically translates long names of files and folders to 8.3 names for MS-DOS and Windows 3.x users.

See also: file allocation table (FAT); MS-DOS (Microsoft Disk Operating System)


Make Changes

The Macintosh-style permission that gives users the right to make changes to a folder's contents; for example, modifying, renaming, moving, creating, and deleting files. When AppleTalk network integration translates access privileges into permissions, a user who has the Make Changes privilege is given Write and Delete permissions.

See also: permission

master boot record (MBR)

The first sector on a hard disk, which starts the process of booting the computer. The MBR contains the partition table for the disk and a small amount of executable code called the master boot code.

See also: Recovery Console

Master File Table (MFT)

An NTFS system file on NTFS-formatted volumes that contains information about each file and folder on the volume. The MFT is the first file on an NTFS volume.

See also: file allocation table (FAT); NTFS file system; volume

master server

An authoritative DNS server for a zone. Master servers can vary and are one of two types (either primary or secondary masters), depending on how the server obtains its zone data.


To enlarge a window to its largest size by clicking the Maximize button (at the right of the title bar), or by pressing ALT+SPACEBAR and then pressing X.

See also: minimize; title bar


Any fixed or removable objects that store computer data. Examples include hard disks, floppy disks, tapes, and compact discs.

megabyte (MB)

1,048,576 bytes, though often interpreted as 1 million bytes.

See also: gigabyte (GB); kilobyte (KB)


Generally, the fast semiconductor storage (RAM) directly connected to the processor that depends on electrical power for activation. Memory is often differentiated from computer storage (for example, hard disks, floppy disks, and CD-ROM disks) that does not depend on electricity and is therefore a more permanent means for holding data.

memory address

A portion of computer memory that can be allocated to a device or used by a program or the operating system. Devices are usually allocated a range of memory addresses.

See also: device

Message Queuing

A message queuing and routing system for Windows that enables distributed applications running at different times to communicate across heterogeneous networks and with computers that may be offline. Message Queuing provides guaranteed message delivery, efficient routing, security, and priority-based messaging. Message Queuing was formerly known as MSMQ.

Messenger service

A service that sends and receives messages sent by administrators or by the Alerter service.

See also: service


Data about data. For example, the title, subject, author, and size of a file constitute the file's metadata.

Microsoft Reserved (MSR) partition

A required partition on every GUID partition table (GPT) disk. System components can allocate portions of the MSR partition into new partitions for their own use. For example, when you convert a basic GPT disk to dynamic, the system allocates a portion of the MSR partition to be used as the Logical Disk Manager (LDM) metadata partition. The MSR partition varies in size based on the size of the GPT disk. For disks smaller than 16 GB, the MSR partition is 32 MB. For disks larger than 16 GB, the MSR partition is 128 MB. The MSR partition is not visible in Disk Management, and you cannot store data on the MSR partition or delete it.

See also: partition


To reduce a window to a button on the taskbar by clicking the Minimize button (at the right of the title bar), or by pressing ALT+SPACEBAR and then pressing N.

See also: maximize; title bar

mirrored volume

A fault-tolerant volume that duplicates data on two physical disks. A mirrored volume provides data redundancy by using two identical volumes, which are called mirrors, to duplicate the information contained on the volume. A mirror is always located on a different disk. If one of the physical disks fails, the data on the failed disk becomes unavailable, but the system continues to operate in the mirror on the remaining disk. You can create mirrored volumes only on dynamic disks.

See also: dynamic disk; dynamic volume; RAID-5 volume; volume

modem (modulator/demodulator)

A device that allows computer information to be transmitted and received over a telephone line. The transmitting modem translates digital computer data into analog signals that can be carried over a phone line. The receiving modem translates the analog signals back to digital form.

See also: modem compression; null modem cable; port; Telephony API (TAPI); Waiting for Call

modem compression

A technique used to reduce the number of characters transmitted without losing data content. The transmitting modem compresses the data and the receiving computer or modem decompresses the data back to its original state.

See also: modem (modulator/demodulator)

modulation standards

Protocols that determine how modems convert digital data into analog signals that can be transmitted over telephone lines.

Initially, Bell created modulation standards used in the United States, and the CCITT created international recommendations. The ITU-T (formerly called the CCITT) now makes recommendations generally adopted by modem manufacturers both internationally and in the United States. The ITU-T V series recommendations (such as V.34 and V.90) define data communication over the telephone network. The suffixes -bis and -ter (for example, V.32bis) indicate later versions.

See also: V.34; V.90


The main circuit board of a microcomputer. The motherboard contains the connectors for attaching additional boards.


To place a removable tape or disc into a drive.

See also: dismount; library; mounted drive

mounted drive

A drive attached to an empty folder on an NTFS volume. Mounted drives function the same as any other drive, but are assigned a label or name instead of a drive letter. The mounted drive's name is resolved to a full file system path instead of just a drive letter. Members of the Administrators group can use Disk Management to create mounted drives or reassign drive letters.

See also: drive; mount; NTFS file system; volume


A keyboard feature that enables you to use the numeric keypad to move the mouse pointer and to click, double-click, and drag.

See also: StickyKeys; ToggleKeys; FilterKeys

MS-DOS (Microsoft Disk Operating System)

An operating system used on all personal computers and compatibles. As with other operating systems, such as OS/2, it translates user keyboard input into operations the computer can perform. MS-DOS can be easily accessed by using the command prompt, while MS-DOS-based programs can be accessed through the use of shortcuts on the desktop.

See also: command prompt window; MS-DOS-based program; OS/2

MS-DOS icon

The icon at the left end of the title bar. Clicking this icon displays the System menu for the MS-DOS window.

MS-DOS-based program

A program that is designed to run with MS-DOS and therefore may not be able to take full advantage of all Windows features.

See also: MS-DOS (Microsoft Disk Operating System); program information file (PIF)

multihomed computer

A computer that has multiple network adapters or that has been configured with multiple IP addresses for a single network adapter.

See also: virtual IP address; IP address; network adapter

multilink dialing

The combination of two or more physical communications links' bandwidth into a single logical link to increase your remote access bandwidth and throughput by using remote access Multilink. Based on the Internet Engineering Task Force (IETF) standard RFC 1990, Multilink combines analog modem paths, ISDN B-channels, and mixed analog and digital communications links on both your client and server computers. This increases your Internet and intranet access speed and decreases the amount of time you are connected to a remote computer.

See also: bandwidth; Integrated Services Digital Network (ISDN)

multiple boot

A computer configuration that runs two or more operating systems.

See also: dual boot; startup environment

My Documents

A folder that provides you with a convenient place to store documents, graphics, or other files you want to access quickly. When you save a file in a program such as WordPad or Paint, the file is automatically saved in My Documents, unless you choose a different folder.

See also: home folder


name resolution

The process of having software translate between names that are easy for users to work with and numerical IP addresses, which are difficult for users but necessary for TCP/IP communications. Name resolution can be provided by software components such as DNS or WINS.

See also: Domain Name System (DNS); Transmission Control Protocol/Internet Protocol (TCP/IP)


A set of unique names for resources or items used in a shared computing environment.

For Microsoft Management Console (MMC), the namespace is represented by the console tree, which displays all of the snap-ins and resources that are accessible to a console.

For Domain Name System (DNS), namespace is the vertical or hierarchical structure of the domain name tree. For example, each domain label, such as host1 or example, used in a fully qualified domain name, such as, indicates a branch in the domain namespace tree.

See also: console tree; Domain Name System (DNS); label; resource; snap-in

NetBIOS Extended User Interface (NetBEUI)

A network protocol native to Microsoft Networking. It is usually used in small, department-size local area networks (LANs) of 1 to 200 clients. It can use Token Ring source routing as its only method of routing. It is the Microsoft implementation of the NetBIOS standard.

See also: local area network (LAN); protocol


A group of computers and other devices, such as printers and scanners, connected by a communications link, enabling all the devices to interact with each other. Networks can be small or large, permanently connected through wires or cables, or temporarily connected through phone lines or wireless transmissions. The largest network is the Internet, which is a worldwide group of networks.

See also: network adapter

network adapter

A device that connects your computer to a network. This device is sometimes called an adapter card or network interface card.

network administrator

A person responsible for planning, configuring, and managing the day-to-day operation of the network. Network administrator is also called a system administrator.

network card driver

A device driver that works directly with the network card, acting as an intermediary between the card and the protocol driver. With AppleTalk network integration, the AppleTalk Protocol stack on the server is implemented as a protocol driver and is bound to one or more network card drivers.

See also: device driver

Network Name resource

The name of a device that exists on a network and is supported as a cluster resource by a Resource DLL provided with Windows.

See also: Resource DLL

Network News Transfer Protocol (NNTP)

A member of the TCP/IP suite of protocols used to distribute network news messages to NNTP servers and clients (newsreaders) on the Internet. NNTP is designed so that news articles are stored on a server in a central database, thus enabling a user to select specific items to read.

See also: Transmission Control Protocol/Internet Protocol (TCP/IP)

network partition

A state in which one or more of the nodes in a cluster cannot communicate with the other cluster nodes.

network password

A password that you use to log on to a network. You can make this the same as your Windows password, so you have only one password to remember.

network protocol

The language a computer uses to communicate over a network. For a computer to communicate with another computer, they both must use the same protocol.

network service

Services such as file and printer sharing on your computer or automatic backup to a network server.

non-Plug and Play

A device, such as a printer, modem, or game controller, that requires manual configuration of hardware settings before it can be used. Non-Plug and Play devices are becoming increasingly rare as manufacturers stop producing them in favor of Plug and Play devices. Non-Plug and Play typically applies to older pieces of equipment.

See also: device; Plug and Play

notification area

The area on the taskbar to the right of the taskbar buttons. The notification area displays the time and can also contain shortcuts that provide quick access to programs, such as Volume Control and Power Options. Other shortcuts can appear temporarily, providing information about the status of activities. For example, the printer shortcut icon appears after a document has been sent to the printer and disappears when printing is complete.

NTFS file system

An advanced file system that provides performance, security, reliability, and advanced features that are not found in any version of FAT. For example, NTFS guarantees volume consistency by using standard transaction logging and recovery techniques. If a system fails, NTFS uses its log file and checkpoint information to restore the consistency of the file system. In Windows 2000 and Windows XP, NTFS also provides advanced features such as file and folder permissions, encryption, disk quotas, and compression.

See also: FAT32; file allocation table (FAT); file system

null modem cable

Special cabling that eliminates the modem's need for asynchronous communications between two computers over short distances. A null modem cable emulates modem communication.

See also: modem (modulator/demodulator)

number system

Any system for representing numbers. The four number systems available are decimal, hexadecimal, octal, and binary.



An entity, such as a file, folder, shared folder, printer, or Active Directory object, described by a distinct, named set of attributes. For example, the attributes of a File object include its name, location, and size; the attributes of an Active Directory User object might include the user's first name, last name, and e-mail address.

For OLE and ActiveX, an object can also be any piece of information that can be linked to, or embedded into, another object.

See also: attribute; OLE


A state that marks a component in a cluster as unavailable. A node in an offline state is either inactive or not running. Resources and groups also have an offline state.

See also: group; online; resource


A way to transfer and share information between applications by pasting information created in one application into a document created in another application, such as a spreadsheet or word processing file.

See also: embedded object; linked object; package


A state that marks a component in a cluster as available. When a node is online, it is an active member of the cluster and can own and run groups as well as honor cluster database updates, contribute votes to the quorum algorithm, and maintain heartbeats. Resources and groups also have an online state.

See also: group; offline; resource

OpenType fonts

Outline fonts that are rendered from line and curve commands, and can be scaled and rotated. OpenType fonts are clear and readable in all sizes and on all output devices supported by Windows. OpenType is an extension of TrueType font technology.

See also: font; TrueType fonts


In mathematics and in programming and computer applications, a symbol or other character indicating an operation that acts on one or more elements. You can use the following four operators in standard calculations:

/ divide
* multiply
- subtract
+ add

For Indexing Service, a word or character that specifies a relationship in a query.

orphan file

A file that is stored inside My Briefcase and not linked to any file outside My Briefcase. When you update files, the orphan file is not synchronized with any other file.


A protected-mode, virtual memory, multitasking operating system for personal computers based on the Intel 80286, 80386, i486, and Pentium processors. OS/2 can run most MS-DOS-based programs and can read all MS-DOS disks.

See also: MS-DOS-based program



An icon that represents embedded or linked information. That information may consist of a complete file, such as a Paint bitmap, or part of a file, such as a spreadsheet cell. When you choose the package, the application used to create the object either plays the object (for example, a sound file) or opens and displays the object. If you change the original information, linked information is automatically updated. However, you must manually update embedded information.

See also: embedded object; linked object; OLE


An Open Systems Interconnection (OSI) network layer transmission unit that consists of binary information representing both data and a header containing an identification number, source and destination addresses, and error-control data.

See also: Internet Protocol (IP); switching hub

page fault

The interrupt that occurs when software attempts to read from or write to a virtual memory location that is marked not present.

In Task Manager, page fault is the number of times data has to be retrieved from disk for a process because it was not found in memory. The page fault value accumulates from the time the process started.

See also: Page Faults Delta; Task Manager; virtual memory

Page Faults Delta

In Task Manager, the change in the number of page faults since the last update.

See also: Task Manager

page-description language (PDL)

A computer language that describes the arrangement of text and graphics on a printed page.

See also: Printer Control Language (PCL); Printer Job Language (PJL); PostScript; PostScript fonts

paged pool

The system-allocated virtual memory that has been charged to a process and that can be paged. Paging is the moving of infrequently-used parts of a program's working memory from RAM to another storage medium, usually the hard disk.

In Task Manager, the amount of system-allocated virtual memory, in kilobytes, used by a process.

See also: virtual memory

paging file

A hidden file on the hard disk that Windows uses to hold parts of programs and data files that do not fit in memory. The paging file and physical memory, or RAM, comprise virtual memory. Windows moves data from the paging file to memory as needed and moves data from memory to the paging file to make room for new data. Paging file is also called a swap file.

See also: Peak Memory Usage; virtual memory


A font-classification method that measures values, such as serifs, weight, and stroke variations, for a TrueType font. These values are represented by a Panose number. The Panose number is then used to associate the font with other fonts of similar appearance but different names. The closer the Panose number of two fonts, the more similar they are.

parallel port

The input/output connector for a parallel interface device. Printers are generally plugged into a parallel port.

See also: serial port


A calculated value that is used to reconstruct data after a failure. RAID-5 volumes stripe data and parity intermittently across a set of disks. When a disk fails, some server operating systems use the parity information together with the data on good disks to recreate the data on the failed disk.

See also: RAID-5 volume


A portion of a physical disk that functions as though it were a physically separate disk. After you create a partition, you must format it and assign it a drive letter before you can store data on it.

On basic disks, partitions are known as basic volumes, which include primary partitions and logical drives. On dynamic disks, partitions are known as dynamic volumes, which include simple, striped, spanned, mirrored, and RAID-5 volumes.

See also: basic disk; basic volume; drive letter; dynamic volume; extended partition; primary partition; system partition


A security measure used to restrict logon names to user accounts and access to computer systems and resources. A password is a string of characters that must be provided before a logon name or an access is authorized. A password can be made up of letters, numbers, and symbols, and it is case sensitive.

See also: user account

PC Card

A removable device, approximately the size of a credit card, that can be plugged into a Personal Computer Memory Card International Association (PCMCIA) slot in a portable computer. PCMCIA devices can include modems, network cards, and hard disk drives.

See also: modem (modulator/demodulator)

PCI expansion slot

A connection socket for a peripheral designed for the Peripheral Component Interconnect (PCI) local bus on a computer motherboard.

PCMCIA device

A removable device, approximately the size of a credit card, that can be plugged into a PCMCIA slot in a portable computer. PCMCIA devices can include modems, network adapters, and hard disk drives.

Some PCMCIA cards can be connected to and disconnected from your computer without restarting it. Before you remove the PCMCIA card, however, you should use the Add Hardware Wizard to notify Windows that you are doing so. Windows will then notify you when you can remove the device.

Peak Memory Usage

In Task Manager, the peak amount of physical memory resident in a process since it started.

See also: Task Manager


A device, such as a disk drive, printer, modem, or joystick, that is connected to a computer and is controlled by the computer's microprocessor.

See also: device

peripheral component interconnect (PCI)

A specification introduced by Intel Corporation that defines a local bus system that allows up to 10 PCI-compliant expansion cards to be installed in the computer.


A rule associated with an object to regulate which users can gain access to the object and in what manner. Permissions are granted or denied by the object's owner.

See also: special access permissions; object; printer permissions; shared folder permissions


Short for picture element, one spot in a rectilinear grid of thousands of such spots that form an image produced on the screen by a computer or on paper by a printer. A pixel is the smallest element that display or print hardware and software can manipulate to create letters, numbers, or graphics. A pixel is also called a pel.

See also: screen resolution

PKCS #12

The Personal Information Exchange Syntax Standard, developed and maintained by RSA Data Security, Inc. This syntax standard specifies a portable format for storing or transporting a user's private keys, certificates, and miscellaneous secrets.

See also: certificate


The Cryptographic Message Syntax Standard. It is a general syntax, developed and maintained by RSA Data Security, Inc., for data to which cryptography may be applied, such as digital signatures and encryption. It also provides a syntax for disseminating certificates or certificate revocation lists.

See also: certificate; certificate revocation list (CRL); encryption


Data that is not encrypted. Sometimes also called cleartext.


Any device used to draw charts, diagrams, and other line-based graphics.

plotter font

A font created by a series of dots connected by lines. Plotter fonts can be scaled to any size and are most often printed on plotters. Some dot-matrix printers also support plotter fonts.

See also: font

Plug and Play

A set of specifications developed by Intel that allows a computer to automatically detect and configure a device and install the appropriate device drivers.

See also: universal serial bus (USB); non-Plug and Play

Point-to-Point Protocol (PPP)

An industry standard suite of protocols for the use of point-to-point links to transport multiprotocol datagrams. PPP is documented in RFC 1661.

See also: Transmission Control Protocol/Internet Protocol (TCP/IP)

Point-to-Point Protocol over Ethernet (PPPoE)

A specification for connecting users on an Ethernet network to the Internet through a broadband connection, such as a single DSL line, wireless device, or cable modem. Using PPPoE and a broadband modem, LAN users can gain individual authenticated access to high-speed data networks. By combining Ethernet and Point-to-Point Protocol (PPP), PPPoE provides an efficient way to create a separate connection for each user to a remote server.

Point-to-Point Tunneling Protocol (PPTP)

Networking technology that supports multiprotocol virtual private networks (VPNs), enabling remote users to access corporate networks securely across the Internet or other networks by dialing into an Internet service provider (ISP) or by connecting directly to the Internet. The Point-to-Point Tunneling Protocol (PPTP) tunnels, or encapsulates, IP, IPX, or NetBEUI traffic inside of IP packets. This means that users can remotely run applications that are dependent upon particular network protocols.

See also: Internet Protocol (IP); NetBIOS Extended User Interface (NetBEUI); packet; tunnel; virtual private network (VPN)


The mechanism by which desktop settings are configured automatically, as defined by the administrator. Depending on context, this can refer to Group Policy, Windows NT 4.0 System Policy, or a specific setting in a Group Policy object.

See also: Group Policy; Group Policy object


A connection point on your computer where you can connect devices that pass data into and out of a computer. For example, a printer is typically connected to a parallel port (also called an LPT port), and a modem is typically connected to a serial port (also called a COM port).

See also: serial port; universal serial bus (USB)


A page-description language (PDL), developed by Adobe Systems for printing on laser printers. PostScript offers flexible font capability and high-quality graphics. It is the standard for desktop publishing because it is supported by imagesetters, the high-resolution printers used by printing services for commercial typesetting.

See also: Printer Control Language (PCL); page-description language (PDL); Printer Job Language (PJL); PostScript fonts; PostScript printer; service; Type 1 fonts

PostScript fonts

Fonts that are defined in terms of the PostScript page-description language (PDL) rules and are intended to be printed on a PostScript-compatible printer. When a document displayed in a screen font is sent to a PostScript printer, the printer uses the PostScript version if the font exists. If the font doesn't exist but a version is installed on the computer, that font is downloaded to the printer. If there is no PostScript font installed in either the printer or the computer, the bit-mapped (raster) font is translated into PostScript and the printer produces text using the bit-mapped font. PostScript fonts are distinguished from bit-mapped fonts by their smoothness, detail, and faithfulness to standards of quality established in the typographic industry.

See also: downloadable fonts; font; page-description language (PDL); PostScript; raster fonts

PostScript printer

A printer that uses the PostScript page-description language (PDL) to create text and graphics on the output medium, such as paper or overhead transparency. Examples of PostScript printers include the Apple LaserWriter, the NEC LC-890, and the QMS PS-810.

See also: page-description language (PDL); PostScript; virtual printer memory

power scheme

A group of preset power-management options. For example, you can set elapsed times for putting your computer on standby and for turning off your monitor and hard disk. You save these settings as a named power scheme.

PPP (Point-to-Point Protocol)

See definition for: Point-to-Point Protocol (PPP)

preset-to callback

A form of security in which a remote access server verifies users by calling them back at numbers supplied by the network administrator at the time user privileges are granted. Only a network administrator can change a preset callback number. This ensures that no one can borrow a user's password and connect to the server from a location other than the user's normal one.

See also: connected, user authenticated

Primary disk

The hard disk drive that contains the system and boot partitions used to start Windows.

See also: boot partition; system partition

primary mouse button

The button you use most often for clicking and double-clicking. The primary mouse button is the left button on most mice and trackball devices, and the lower button on some trackball devices, but you can switch the function of the buttons by using the Mouse Properties dialog box in Control Panel.

primary partition

A type of partition that you can create on basic disks. A primary partition is a portion of a physical disk that functions as though it were a physically separate disk. On basic master boot record (MBR) disks, you can create up to four primary partitions on a basic disk, or three primary partitions and an extended partition with multiple logical drives. On basic GPT disks, you can create up to 128 primary partitions. Primary partitions are also known as volumes.

See also: basic disk; extended partition; logical drive; master boot record (MBR); partition; volume

print job

The source code that contains both the data to be printed and the commands for print. Print jobs are classified into data types based on what modifications, if any, the spooler must make to the job for it to print correctly.

See also: print spooler; Printer window; printing pool

print processor

The component that, working in conjunction with the printer driver, receives and alters print jobs, as necessary, according to their data type to ensure that the jobs print correctly.

See also: print job; printer driver

print queue

A print queue is a list of documents waiting to be printed on the printer. In the print queue, you can see information such as the size of the document, who sent the document, and status information for printing.

print server

A computer that is dedicated to managing the printers on a network. The print server can be any computer on the network.

print spooler

Software that accepts a document sent to a printer and then stores it on disk or in memory until the printer is ready for it. This collection of dynamic-link libraries (DLLs) receives, processes, schedules, and distributes documents for printing. The term spooler is an acronym created from simultaneous print operations on line.

See also: dynamic-link library (DLL); printer; spooling

Print Spooler resource

Printer queues providing access to a network printer connected to the network by an IP address rather than by an individual name. Print spoolers are supported as cluster resources by a Resource DLL.

See also: print spooler; Resource DLL; IP address


A device that puts text or images on paper or other print media. Examples are laser printers or dot-matrix printers.

See also: logical printer; print spooler; printing pool

Printer Control Language (PCL)

The page-description language (PDL) developed by Hewlett Packard for their laser and inkjet printers. Because of the widespread use of laser printers, this command language has become a standard in many printers.

See also: page-description language (PDL); Printer Job Language (PJL); PostScript

printer driver

A program designed to allow other programs to work with a particular printer without concerning themselves with the specifics of the printer's hardware and internal language. By using printer drivers that handle the subtleties of each printer, programs can communicate properly with a variety of printers.

See also: device driver

printer fonts

Fonts residing in or intended for a printer. A printer font, usually located in the printer's read-only memory (ROM), can be internal, downloaded, or on a font cartridge.

See also: device fonts; downloadable fonts; font; font cartridge

Printer Job Language (PJL)

The printer command language developed by Hewlett Packard that provides printer control at the print-job level. Using PJL commands, you can change default printer settings such as number of copies to print. PJL commands also permit switching printer languages between print jobs without action by the user. If bi-directional communication is supported, a PJL-compatible printer can send information such as printer model and job status to the print server.

See also: Printer Control Language (PCL); page-description language (PDL); PostScript

printer permissions

Permissions that specify the type of access that a user or group has to a printer. The printer permissions are Print, Manage Printers, and Manage Documents.

See also: permission

Printer window

Also called the queue view, the Printer window shows information about any pending print jobs for the printer. For each printer you have installed or to which you are connected, you can such information as see how many documents are waiting to be printed, who owns them, and how large they are.

See also: print job

Printers and Faxes

The folder in Control Panel that contains the Add Printer Wizard and icons for all the printers installed on your computer.

See also: printer

printing pool

Two or more identical printers that are connected to one print server and act as a single printer. In this case, when you print a document, the print job will be sent to the first available printer in the pool.

See also: print job; printer

private key

The secret half of a cryptographic key pair that is used with a public key algorithm. Private keys are typically used to decrypt a symmetric session key, digitally sign data, or decrypt data that has been encrypted with the corresponding public key.


A user's right to perform a specific task, usually one that affects an entire computer system rather than a particular object. Privileges are assigned by administrators to individual users or groups of users as part of the security settings for the computer.


A complete, self-contained set of computer instructions that you use to perform a specific task, such as word processing, accounting, or data management. Program is also called application.

program information file (PIF)

A file that provides information to Windows about how best to run MS-DOS-based programs. When you start an MS-DOS-based program, Windows looks for a PIF to use with it. PIFs contain such items as the name of the file, a start-up directory, and multitasking options.

See also: MS-DOS-based program


A set of rules and conventions for sending information over a network. These rules govern the content, format, timing, sequencing, and error control of messages exchanged among network devices.

See also: Transmission Control Protocol/Internet Protocol (TCP/IP)

public key cryptography

A method of cryptography in which two different keys are used: a public key for encrypting data and a private key for decrypting data. Public key cryptography is also called asymmetric cryptography.

See also: private key

puff and sip device

An assistive computer technology for people with mobility impairments. A puff and sip device is a head-mounted alternative to using the mouse. The device allows a user to move the mouse pointer without using his or her hands by puffing air into a tube.



A list of programs or tasks waiting for execution. In Windows printing terminology, a queue refers to a group of documents waiting to be printed. In NetWare and OS/2 environments, queues are the primary software interface between the application and print device; users submit documents to a queue. With Windows, however, the printer is that interface; the document is sent to a printer, not a queue.

See also: transactional message; printer

Quick Launch

A customizable toolbar that lets you display the Windows desktop or start a program (for example, Internet Explorer) with a single click. You can add buttons to start your favorite programs from the Quick Launch location on the taskbar.


RAID-5 volume

A fault-tolerant volume with data and parity striped intermittently across three or more physical disks. Parity is a calculated value that is used to reconstruct data after a failure. If a portion of a physical disk fails, Windows recreates the data that was on the failed portion from the remaining data and parity. You can create RAID-5 volumes only on dynamic disks, and you cannot mirror or extend RAID-5 volumes.

See also: dynamic disk; dynamic volume; parity; volume


See definition for: random access memory (RAM)

random access memory (RAM)

Memory that can be read from or written to by a computer or other devices. Information stored in RAM is lost when the computer is turned off.

See also: virtual memory

raster fonts

Fonts that are stored as bitmaps. Raster fonts are designed with a specific size and resolution for a specific printer and cannot be scaled or rotated. If a printer does not support raster fonts, it will not print them. The five raster fonts are Courier, MS Sans Serif, MS Serif, Small, and Symbol. Raster fonts are also called bit-mapped fonts.

See also: font; printer


To restart a computer by reloading the operating system. This can be done by performing either a cold boot, such as turning the computer off and then back on, or a warm boot, such as turning the computer off by typically pressing CTRL + ALT + DEL, clicking Shut Down, and then clicking Restart.

recovery agent

A person who is issued a public key certificate for the purpose of recovering user data that is encrypted with Encrypting File System (EFS).

See also: certificate; Encrypting File System (EFS)

Recovery Console

A command-line interface that provides a limited set of administrative commands that are useful for repairing a computer.

See also: NTFS file system

Recycle Bin

The place in which Windows stores deleted files. You can retrieve files you deleted in error, or you can empty the Recycle Bin to create more disk space.

registered file type

File types that are tracked by the system registry and are recognized by the programs you have installed on your computer.

See also: file type


A database repository for information about a computer's configuration. The registry contains information that Windows continually references during operation, such as:

  • Profiles for each user.
  • The programs installed on the computer and the types of documents each can create.
  • Property settings for folders and program icons.
  • What hardware exists on the system.
  • Which ports are being used.

The registry is organized hierarchically as a tree and is made up of keys and their subkeys, hives, and value entries.

See also: hive; key

relative ID (RID)

The part of a security ID (SID) that uniquely identifies an account or group within a domain.

See also: domain; group; security ID (SID)

Removable Storage

A service used for managing removable media (such as tapes and discs) and storage devices (libraries). Removable Storage allows applications to access and share the same media resources.

See also: library; service

rendering intent

In color management, the approach used to map the colors specified in an image file to the color gamut of your monitor or printer. The color gamut is the range of color that a device can produce.

See also: color gamut

Repeat delay

A delay of the amount of time that elapses before a character begins repeating when you hold down a key.


A folder within a replica set.

See also: replica set

replica set

One or more shared folders that participates in replication.

See also: replication


The process of copying data from a data store or file system to multiple computers to synchronize the data. Active Directory provides multimaster replication of the directory between domain controllers within a given domain. The replicas of the directory on each domain controller are writable. This allows updates to be applied to any replica of a given domain. The replication service automatically copies the changes from a given replica to all other replicas.

See also: Active Directory; replica; topology

Request for Comments (RFC)

An official document of the Internet Engineering Task Force (IETF) that specifies the details for protocols included in the TCP/IP family.

See also: Internet Engineering Task Force (IETF); protocol; Transmission Control Protocol/Internet Protocol (TCP/IP)


A specific IP address within a scope permanently reserved for leased use to a specific DHCP client. Client reservations are made in the DHCP database using DHCP Manager and based on a unique client device identifier for each reserved entry.

In Admission Control Service, an allocation of network resources, contained in a Resource Reservation Protocol (RSVP) reservation request administered by the Admission Control Service.

See also: Dynamic Host Configuration Protocol (DHCP); IP address


DNS client programs used to look up DNS name information. Resolvers can be either a small stub (a limited set of programming routines that provide basic query functionality) or larger programs that provide additional lookup DNS client functions, such as caching.

See also: Domain Name System (DNS)


Generally, any part of a computer system or network, such as a disk drive, printer, or memory, that can be allotted to a running program or a process.

For Device Manager, any of four system components that control how the devices on a computer work. These four system resources are interrupt request (IRQ) lines, direct memory access (DMA) channels, input/output (I/O) ports, and memory addresses.

For server clusters, a physical or logical entity that is capable of being managed by a cluster, brought online and taken offline, and moved between nodes. A resource can be owned only by a single node at any point in time.

See also: input/output (I/O) port; memory address; offline; online; resource

Resource DLL

A dynamic-link library (DLL) containing an implementation of the Resource application programming interface (API) for a specific type of resource. The Resource DLL is loaded into the address space of its Resource Monitor.

See also: dynamic-link library (DLL)

resource domain

A Windows NT 4.0 domain that is used for hosting file, print, and other application services.

See also: domain; service


In Windows remote access, strings expected from the device, which can contain macros.

Restore Point

A representation of a stored state of your computer. Restore point is created by System Restore at specific intervals and when System Restore detects the beginning of a change to your computer. Also, restore point can be created by you manually at any time.


To position the mouse over an object, and then press and release the secondary (right) mouse button. Right-clicking opens a shortcut menu that contains useful commands, which change depending on where you click.


An acronym for Read-Only Memory, a semiconductor circuit into which code or data is permanently installed by the manufacturing process. ROM contains instructions or data that can be read but not modified.


The highest or uppermost level in a hierarchically organized set of information. The root is the point from which further subsets are branched in a logical sequence that moves from a broad or general focus to narrower perspectives.

root authority

The certification authority (CA) at the top of a certification hierarchy. The root CA has a self-signed certificate. Also called the root certification authority.

See also: certification authority (CA); certification hierarchy; root

root certificate

A self-signed certification authority certificate. It is called a root certificate because it is the certificate for the root authority. The root authority must sign its own certificate because by definition there is no higher certifying authority in the certification hierarchy.

See also: certificate; certification authority (CA); certification hierarchy; root authority


In a Windows environment, hardware that helps LANs and WANs achieve interoperability and connectivity, and can link LANs that have different network topologies (such as Ethernet and Token Ring). Routers match packet headers to a LAN segment and choose the best path for the packet, optimizing network performance.

In the Macintosh environment, routers are necessary for computers on different physical networks to communicate with each other. Routers maintain a map of the physical networks on a Macintosh internet (network) and forward data received from one physical network to other physical networks. Computers running the Server version of Windows with AppleTalk network integration can act as routers, and you can also use other routing hardware on a network with AppleTalk network integration.

See also: local area network (LAN); routing; wide area network (WAN)


The process of forwarding a packet through an internetwork from a source host to a destination host.

See also: host; packet



In color management, the purity of a color's hue, moving from gray to the pure color.

See also: hue


A file that is created when you drag part of a document to the desktop.

screen fonts

A typeface designed for display on a computer monitor screen. Screen fonts often have accompanying PostScript fonts for printing to PostScript-compatible printers.

See also: font; PostScript

screen resolution

The setting that determines the amount of information that appears on your screen, measured in pixels. Low resolution, such as 640 x 480, makes items on the screen appear large, although the screen area is small. High resolution, such as 1024 x 768, makes the overall screen area large, although individual items appear small.

See also: pixel


A type of program consisting of a set of instructions to an application or tool program. A script usually expresses instructions by using the application's or tool's rules and syntax, combined with simple control structures such as loops and if/then expressions. "Batch program" is often used interchangeably with "script" in the Windows environment.

script file

A script file contains scripting commands, parameters, and expressions that provide information to, and retrieve it from, the remote computer you are connecting to. This information includes your user name and password, port information, carriage returns, line feeds, and pauses.

Secure Sockets Layer (SSL)

A proposed open standard for establishing a secure communications channel to prevent the interception of critical information, such as credit card numbers. Primarily, it enables secure electronic financial transactions on the World Wide Web, although it is designed to work on other Internet services as well.

Secure/Multipurpose Internet Mail Extensions (S/MIME)

An extension of MIME to support secure mail. It enables message originators to digitally sign e-mail messages to provide proof of message origin and data integrity. It also enables messages to be transmitted in encrypted format to provide confidential communications.

security group

A group that can be listed in discretionary access control lists (DACLs) used to define permissions on resources and objects. A security group can also be used as an e-mail entity. Sending an e-mail message to the group sends the message to all the members of the group.

security host

An authentication device, supplemental to standard Windows and remote access server security, that verifies whether a caller from a remote client is authorized to connect to the remote access server.

See also: authentication

security ID (SID)

A data structure of variable length that identifies user, group, and computer accounts. Every account on a network is issued a unique SID when the account is first created. Internal processes in Windows refer to an account's SID rather than the account's user or group name.

See also: group account; group name; user account; user name

security principal

An account holder that is automatically assigned a security identifier for access to resources. A security principal can be a user, group, service, or computer.

See also: group; security principal name; service

security principal name

A name that uniquely identifies a user, group, or computer within a single domain. This name is not guaranteed to be unique across domains.

See also: domain; group; security principal


To specify a block of data or text on screen by highlighting it or otherwise marking it, with the intent of performing some operation on it.

serial port

An interface on the computer that allows asynchronous transmission of data characters one bit at a time. Also called a communication or COM port.

See also: communication port; port

SerialKey device

Enables you to attach an alternate input device (also called an augmentative communication device) to your computer's serial port. This feature is designed for people who are unable to use the computer's standard keyboard and mouse.


In general, a computer that provides shared resources to network users.

See also: client; shared resource

Server Message Block (SMB)

A file-sharing protocol designed to allow networked computers to transparently access files that reside on remote systems over a variety of networks. The SMB protocol defines a series of commands that pass information between computers. SMB uses four message types: session control, file, printer, and message.


A program, routine, or process that performs a specific system function to support other programs, particularly at a low (close to the hardware) level. When services are provided over a network, they can be published in Active Directory, facilitating service-centric administration and usage. Some examples of services are the Security Accounts Manager service, File Replication service, and Routing and Remote Access service.

See also: Active Directory; Dynamic Host Configuration Protocol (DHCP); Service Profile Identifier (SPID)

Service Profile Identifier (SPID)

An 8-digit to 14-digit number that identifies the services that you ordered for each B-channel. For example, when you order Primary Rate ISDN, you obtain two phone numbers and two SPIDs from your ISDN provider. Typical ISDN adapters cannot operate without configuring SPIDs.

See also: Integrated Services Digital Network (ISDN); service

set-by-caller callback

In Network Connections, a form of callback in which the user supplies the telephone number that the remote access server uses for callback. This setting spares the user any long-distance telephone charges.

See also: connected, user authenticated


To make resources, such as folders and printers, available to others.

See also: resource

shared folder

A folder on another computer that has been made available for other people to use on the network.

shared folder permissions

Permissions that restrict a shared resource's availability over the network to only certain users.

See also: permission

shared printer

A printer that receives input from more than one computer. For example, a printer attached to another computer on the network can be shared so that it is available for you to use. Shared printer is also called a network printer.

See also: printer

shared resource

Any device, data, or program that is used by more than one other device or program. For Windows, shared resources refer to any resource that is made available to network users, such as folders, files, printers, and named pipes. A shared resource can also refer to a resource on a server that is available to network users.

See also: device; resource; server


A link to any item accessible on your computer or on a network, such as a program, file, folder, disk drive, Web page, printer, or another computer. You can put shortcuts in various areas, such as on the desktop, on the Start menu, or in specific folders.

See also: desktop


A feature that instructs programs that usually convey information only by sound to also provide all information visually, such as by displaying text captions or informative icons.

Simple TCP/IP Services

Four TCP/IP services: Character Generator, Daytime Discard, Echo, and Quote of the Day.

See also: service; Transmission Control Protocol/Internet Protocol (TCP/IP)

simple volume

A dynamic volume made up of disk space from a single dynamic disk. A simple volume can consist of a single region on a disk or multiple regions of the same disk that are linked together. You can extend a simple volume within the same disk or onto additional disks. If you extend a simple volume across multiple disks, it becomes a spanned volume. You can create simple volumes only on dynamic disks. Simple volumes are not fault tolerant, but you can mirror them to create mirrored volumes.

See also: dynamic disk; dynamic volume; mirrored volume; spanned volume; volume

single sign-on

A process that allows a user with a domain account to log on to a network once, using a password or smart card, and to gain access to any computer in the domain.

See also: domain; smart card

single switch device

An assistive computer technology for people with mobility impairments. A single switch device allows users to interact with a computer by using slight body movements.

small computer system interface (SCSI)

A standard high-speed parallel interface defined by the American National Standards Institute (ANSI). A SCSI interface is used for connecting microcomputers to peripheral devices such as hard disks and printers, and to other computers and local area networks (LANs).

See also: device; local area network (LAN)

smart card

A credit card-sized device that is used with an access code to enable certificate-based authentication and single sign-on to the enterprise. Smart cards securely store certificates, public and private keys, passwords, and other types of personal information. A smart card reader attached to the computer reads the smart card.

See also: authentication; single sign-on; smart card reader

smart card reader

A device that is installed in computers to enable the use of smart cards for enhanced security features.

See also: smart card


A type of tool you can add to a console supported by Microsoft Management Console (MMC). A stand-alone snap-in can be added by itself; an extension snap-in can only be added to extend the function of another snap-in.

Sound card

Accessory expansion board for personal computers that permits recording and playing back sound.

sound file

A sound file contains information that Windows uses to play sounds on your computer. Sound files have the file name extension .wav.


A Windows feature that produces a visual cue, such as a screen flash or a blinking title bar, whenever the computer plays a system sound.

source document

The document where a linked or embedded object was originally created.

See also: embedded object; linked object

spanned volume

A dynamic volume consisting of disk space on more than one physical disk. You can increase the size of a spanned volume by extending it onto additional dynamic disks. You can create spanned volumes only on dynamic disks. Spanned volumes are not fault tolerant and cannot be mirrored.

See also: dynamic disk; dynamic volume; mirrored volume; simple volume; volume

special access permissions

On NTFS volumes, a custom set of permissions. You can customize permissions on files and directories by selecting the individual components of the standard sets of permissions.

See also: permission; NTFS file system; volume


A process on a server in which print documents are stored on a disk until a printer is ready to process them. A spooler accepts each document from each client, stores it, then sends it to a printer when the printer is ready.

See also: print spooler


A state in which your computer consumes less power when it is idle, but remains available for immediate use. While your computer is on standby, information in computer memory is not saved on your hard disk. If there is an interruption in power, the information in memory is lost.

startup environment

In dual-boot or multiple-boot systems, the configuration settings that specify which system to start and how each system should be started.

See also: dual boot; multiple boot

static dialog box

A scripted dialog box between the client computer and an intermediary device. This kind of dialog box requires no response from the user.

See also: client

status area

See definition for: notification area


A keyboard feature that enables you to press a modifier key (CTRL, ALT, or SHIFT), or the Windows logo key, and have it remain active until a non-modifier key is pressed. This is useful for people who have difficulty pressing two keys simultaneously.

See also: FilterKeys; MouseKeys; ToggleKeys


A key within a key. In the registry structure, subkeys are subordinate to subtrees and keys. Keys and subkeys are similar to the section header in .ini files; however, subkeys can carry out functions.

See also: registry; key; subkey

subnet mask

A 32-bit value that enables the recipient of IP packets to distinguish the network ID and host ID portions of the IP address. Typically, subnet masks use the format 255.x.x.x.

switch type

The type of interface to which your ISDN device is being attached. Switch type is also called switch.

See also: Integrated Services Digital Network (ISDN)

switching hub

A central network device (multiport hub) that forwards packets to specific ports rather than, as in conventional hubs, broadcasting every packet to every port. In this way, the connections between ports deliver the full bandwidth available.

See also: hub; packet

symmetric encryption

An encryption algorithm that requires the same secret key to be used for both encryption and decryption. Because of its speed, symmetric encryption is typically used when a message sender needs to encrypt large amounts of data. Symmetric encryption is also called secret key encryption.


To reconcile the differences between files stored on one computer and versions of the same files on another computer. Once the differences are determined, both sets of files are updated.

system access control list (SACL)

The part of an object's security descriptor that specifies which events are to be audited per user or group. Examples of auditing events are file access, logon attempts, and system shutdowns.

See also: object

system disk

A disk that contains the MS-DOS system files necessary to start MS-DOS.

See also: MS-DOS (Microsoft Disk Operating System)

system partition

The partition that contains the hardware-specific files needed to load Windows (for example, Ntldr, Osloader, Boot.ini, The system partition can be, but does not have to be, the same as the boot partition.

See also: boot partition; partition

system queue

For Message Queuing, a queue that stores various types of administrative messages. Message Queuing uses up to five system queues, all of which are private queues. System queues cannot be deleted.

See also: queue; Message Queuing; system queue

System Restore

A tool that tracks changes to your computer and creates a restore point when it detects the beginning of a change. You can use the System Restore Wizard to select a restore point to restore your computer to an earlier state when your computer was functioning the way you like.

system volume

The volume that contains the hardware-specific files that are needed to load Windows on x86-based computers with a BIOS. The system volume can be, but does not have to be, the same volume as the boot volume.

See also: basic input/output system (BIOS); boot volume; volume; x86


The path and folder name where the Windows system files are located. Typically, this is C:\Windows, although you can designate a different drive or folder when you install Windows. You can use the value %systemroot% to replace the actual location of the folder that contains the Window system files. To identify your systemroot folder, click Start, click Run, type %systemroot%, and then click OK.



Part of a dialog box that resembles a notebook or file divider and provides navigation between different sections of information in the dialog box.

Task Manager

A utility that provides information about programs and processes running on the computer. Using Task Manager, you can end or run programs and end processes, and display a dynamic overview of your computer's performance.


The bar that contains the Start button and appears by default at the bottom of the desktop. You can click the taskbar buttons to switch between programs. You can also hide the taskbar, move it to the sides or top of the desktop, and customize it in other ways.

See also: desktop; taskbar button; notification area

taskbar button

A button that appears on the taskbar and corresponds to a running application.

See also: taskbar


Telephony API (TAPI)

An application programming interface (API) used by communications programs to work with telephony and network services. Communications programs like HyperTerminal and Phone Dialer use TAPI to dial, answer, and route telephone calls on conventional telephony devices, including PBXs, modems, and fax machines. TAPI 3.0 also provides Internet Protocol (IP) telephony support, which Phone Dialer and other programs use to transmit, route, and control real-time audio and video signals over IP-based networks such as the Internet.

See also: service; Internet Protocol (IP); modem (modulator/demodulator)


A terminal-emulation protocol that is widely used on the Internet to log on to network computers. Telnet also refers to the application that uses the Telnet protocol for users who log on from remote locations.

See also: protocol

text service

A program that enables a user to enter or edit text. Text services include keyboard layouts, handwriting and speech recognition programs, and Input Method Editors (IMEs). IMEs are used to enter East Asian language characters with a keyboard.

Thread Count

In Task Manager, the number of threads running in a process.

See also: Task Manager

three vector fonts

These are Modern, Roman, and Script fonts.


A miniature version of an image that is often used for quick browsing through multiple images.

time server

A computer that periodically synchronizes the time on all computers within a network. This ensures that the time used by network services and local functions remains accurate.

time stamp

A certification by a trusted third party specifying that a particular message existed at a specific time and date. In a digital context, trusted third parties generate a trusted time stamp for a given message by having a time stamping service append a time value to a message and then digitally signing the result.

See also: digital signature; service

title bar

The horizontal bar at the top of a window that contains the name of the window. On many windows, the title bar also contains the program icon, the Maximize, Minimize, and Close buttons, and the optional ? button for context-sensitive Help. To display a menu with commands such as Restore and Move, right-click the title bar.

See also: maximize; minimize


A feature that sets your keyboard to beep when one of the locking keys (CAPS LOCK, NUM LOCK, or SCROLL LOCK) is turned on or off.

See also: FilterKeys; MouseKeys; StickyKeys; ToggleKeys


In a program in a graphical user interface, a row, column, or block of on-screen buttons or icons. When clicked, these buttons or icons activate certain functions, or tasks, of the program. For example, the toolbar in Microsoft Word contains buttons for, among other actions, changing text to italic or boldface, and for saving or opening a document. Users can often customize toolbars and move them around on the screen.


In Windows, the relationships among a set of network components. In the context of Active Directory replication, topology refers to the set of connections that domain controllers use to replicate information among themselves.

See also: Active Directory; replication


The process of teaching the speech recognition engine to recognize your voice and manner of speaking. The speech engine looks for patterns in the way you speak, enabling it to provide better accuracy when you dictate text. You train the engine by reading text in the training wizard, and continue to train the engine as you dictate text while working.


For Message Queuing, the pairing of two or more actions that are performed together as a single action; the action succeeds or fails as a whole. Using Microsoft Distributed Transaction Coordinator (MS DTC) ensures that either both actions succeed or neither is executed.

See also: Message Queuing; transaction dead-letter queue; transactional message

transaction dead-letter queue

For Message Queuing, a queue that stores transactional messages that cannot reach their destination queue. Transaction dead-letter queues store failed messages on the computer on which the message expired. Messages in these queues are written to disk and are therefore recoverable.

See also: Message Queuing; transaction; queue

transactional message

For Message Queuing, a message that can be sent and received only from within a transaction. This type of message returns to its prior state when a transaction is terminated abruptly. A transactional message is removed from a queue only when the transaction is committed; otherwise, it remains in the queue and can be subsequently read during another transaction.

See also: Message Queuing; transaction; queue


A device that can both transmit and receive signals. On local area networks (LANs), a transceiver is the device that connects a computer to the network and that converts signals to and from parallel and serial form.

Transmission Control Protocol/Internet Protocol (TCP/IP)

A set of networking protocols widely used on the Internet that provides communications across interconnected networks of computers with diverse hardware architectures and various operating systems. TCP/IP includes standards for how computers communicate and conventions for connecting networks and routing traffic.

See also: Internet Protocol (IP); protocol

transmitting station ID (TSID) string

A string that specifies the transmitter subscriber ID sent by the fax machine when sending a fax to a receiving machine. This string is usually a combination of the fax or telephone number and the name of the business. It is often the same as the called subscriber ID.

See also: called subscriber ID (CSID) string

Transport Layer Security (TLS)

A standard protocol that is used to provide secure Web communications on the Internet or intranets. It enables clients to authenticate servers or, optionally, servers to authenticate clients. It also provides a secure channel by encrypting communications. TLS is the latest and a more secure version of the SSL protocol.

See also: Secure Sockets Layer (SSL); authentication; protocol


In Simple Network Management Protocol (SNMP), a message sent by an agent to a management system indicating that an event has occurred on the host running the agent.

See also: host

TrueType fonts

Fonts that are scalable and sometimes generated as bitmaps or soft fonts, depending on the capabilities of your printer. TrueType fonts are device-independent fonts that are stored as outlines. They can be sized to any height, and they can be printed exactly as they appear on the screen.

See also: font

trust relationship

A logical relationship established between domains to allow pass-through authentication, in which a trusting domain honors the logon authentications of a trusted domain. User accounts and global groups defined in a trusted domain can be given rights and permissions in a trusting domain, even though the user accounts or groups don't exist in the trusting domain's directory.

See also: permission; authentication; domain; global group; group; user account


A logical connection over which data is encapsulated. Typically, both encapsulation and encryption are performed and the tunnel is a private, secure link between a remote user or host and a private network.

See also: encryption; host; tunnel server

tunnel server

A server or router that terminates tunnels and forwards traffic to the hosts on the target network.

See also: host; router; server; tunnel

Type 1 fonts

Scalable fonts designed to work with PostScript devices.

See also: font; PostScript


A set of characters that share common characteristics, such as stroke width and the presence or absence of serifs (short lines at the upper and lower edges of characters).


unallocated space

Available disk space that is not allocated to any volume. The type of volume that you can create on unallocated space depends on the disk type. On basic disks, you can use unallocated space to create primary or extended partitions. On dynamic disks, you can use unallocated space to create dynamic volumes.

See also: basic disk; dynamic disk; extended partition; logical drive; object; partition; primary partition; volume


To detach a laptop or other portable computer from a docking station.

See also: dock; docking station; hot docking


In data communications networks, to transmit data from one terminal to another, such as from client to server, or from server to server.


A character encoding standard developed by the Unicode Consortium that represents almost all of the written languages of the world. The Unicode character repertoire has multiple representation forms, including UTF-8, UTF-16, and UTF-32. Most Windows interfaces use the UTF-16 form.

See also: American Standard Code for Information Interchange (ASCII); Unicode Character System (UCS); Unicode Transmission Format 8 (UTF-8)

Unicode Character System (UCS)

An international standard character set reference that is part of the Unicode standard. The most widely held existing version of the UCS standard is UCS-2, which specifies 16-bit character values currently accepted and recognized for use to encode most of the world's languages.

See also: Unicode Transmission Format 8 (UTF-8); American Standard Code for Information Interchange (ASCII); Unicode

Unicode Transmission Format 8 (UTF-8)

A character set for protocols evolving beyond the use of ASCII. The UTF-8 protocol provides for support of extended ASCII characters and translation of UCS-2, an international 16-bit Unicode character set. UTF-8 enables a far greater range of names than can be achieved using ASCII or extended ASCII encoding for character data.

See also: American Standard Code for Information Interchange (ASCII); Unicode Character System (UCS); Unicode

Uniform Resource Locator (URL)

An address that uniquely identifies a location on the Internet. A URL for a World Wide Web site is preceded with http://, as in the fictitious URL A URL can contain more detail, such as the name of a page of hypertext, usually identified by the file name extension .html or .htm.


When referring to software, the act of removing program files and folders from your hard disk and removing related data from your registry so the software is no longer available.

When referring to a device, the act of removing the corresponding device drivers from your hard disk and physically removing the device from your computer.

See also: device driver; install

uninterruptible power supply (UPS)

A device connected between a computer and a power source to ensure that electrical flow is not interrupted. UPS devices use batteries to keep the computer running for a period of time after a power failure. UPS devices usually provide protection against power surges and brownouts as well.

universal group

A security or distribution group that can be used anywhere in the domain tree or forest. A universal group can have members from any Windows domain in the domain tree or forest. It can also include other universal groups, global groups, and accounts from any domain in the domain tree or forest. Rights and permissions must be assigned on a per-domain basis, but can be assigned at any domain in the domain tree or forest.

Universal groups can be members of domain local groups and other universal groups, but they cannot be members of global groups. Universal groups appear in the global catalog and should contain primarily global groups.

See also: domain; domain tree; domain local group; global group; security group

universal serial bus (USB)

An external bus that supports Plug and Play installation. Using USB, you can connect and disconnect devices without shutting down or restarting your computer. You can use a single USB port to connect up to 127 peripheral devices, including speakers, telephones, CD-ROM drives, joysticks, tape drives, keyboards, scanners, and cameras. A USB port is usually located on the back of your computer near the serial port or parallel port.

See also: port; bus; Plug and Play

UPS service

A service that manages an uninterruptible power supply (UPS) connected to a computer.

See also: service


See definition for: Uniform Resource Locator (URL)

USB port

An interface on the computer that enables you to connect a Universal Serial Bus (USB) device. USB is an external bus standard that enables data transfer rates of 12 Mbps (12 million bits per second). USB ports support a plug that is approximately 7 mm x 1 mm.

See also: universal serial bus (USB)


A person who uses a computer. If the computer is connected to a network, a user can access the programs and files on the computer, as well as programs and files located on the network (depending on account restrictions determined by the network administrator).

user account

A record that consists of all the information that defines a user to Windows. This includes the user name and password required for the user to log on, the groups in which the user account has membership, and the rights and permissions the user has for using the computer and network, and accessing their resources. For Windows XP Professional and member servers, user accounts are managed with Local Users and Groups. For Windows Server domain controllers, user accounts are managed with Microsoft Active Directory Users and Computers.

See also: permission; Active Directory Users and Computers; group; password; resource; user name

user name

A unique name identifying a user account to Windows. An account's user name must be unique among the other group names and user names within its own domain or workgroup.

See also: domain; group name; user account; workgroup

user password

The password stored in each user's account. Each user generally has a unique user password and must type that password when logging on or accessing a server.

See also: password; user account

user principal name

A user account name (sometimes referred to as the user logon name) and a domain name identifying the domain in which the user account is located. This is the standard usage for logging on to a Windows domain. The format is: (as for an e-mail address).

See also: domain; domain name; user principal name suffix; user account

user principal name suffix

The UPN suffix is the part of the user principal name to the right of the @ character. The default UPN suffix for a user account is the DNS domain name of the domain that contains the user account. Alternative UPN suffixes may be added to simplify administration and user logon processes by providing a single UPN suffix for all users. The UPN suffix is only used within the Active Directory forest and is not required to be a valid DNS domain name.

See also: Active Directory; domain; domain name; Domain Name System (DNS); user principal name; user account

user profile

A file that contains configuration information for a specific user, such as desktop settings, persistent network connections, and application settings. Each user's preferences are saved to a user profile that Windows uses to configure the desktop each time a user logs on.

user rights

Tasks that a user is permitted to perform on a computer system or domain. There are two types of user rights: privileges and logon rights. An example of a privilege is the right to shut down the system. An example of a logon right is the right to log on to a computer locally. Both types are assigned by administrators to individual users or groups as part of the security settings for the computer.

See also: administrator; domain; group; privilege


A special group that contains all users who have user permissions on the server. When a Macintosh user assigns permissions to everyone, those permissions are given to the group's users and guests.

See also: permission; group



Data transmission standard that provides for up to 33,600 bits per second (bps) communications over telephone lines. It defines a full-duplex (two-way) modulation technique and includes error-correcting and negotiation.

See also: bits per second (bps); modulation standards; V.90


Data transmission standard that provides for up to 56,000 bits per second (bps) communications over telephone lines. The transmission speed from the client-side modem is 33,600 bps, the same as V.34. The transmission speed from the host-side modem, such as an Internet service provider (ISP) or corporate network, is up to 56,000 bps, with an average speed of 40,000 to 50,000 bps. When the host-side modem does not support this standard, the alternative is V.34.

See also: bits per second (bps); client; host; Internet service provider (ISP); modem (modulator/demodulator); modulation standards; V.34

vector font

A font rendered from a mathematical model, in which each character is defined as a set of lines drawn between points. Vector fonts can be cleanly scaled to any size or aspect ratio.

See also: font; plotter font

video adapter

An expansion board that plugs into a personal computer to give it display capabilities. A computer's display capabilities depend on both the logical circuitry (provided in the video adapter) and the monitor. Each adapter offers several different video modes. The two basic categories of video modes are text and graphics. Within the text and graphics modes, some monitors also offer a choice of resolutions. At lower resolutions a monitor can display more colors.

Modern adapters contain memory, so that the computer's RAM is not used for storing displays. In addition, most adapters have their own graphics coprocessor for performing graphics calculations. These adapters are often called graphics accelerators.

virtual IP address

An IP address that is shared among the hosts of a Network Load Balancing cluster. A Network Load Balancing cluster might also use multiple virtual IP addresses, for example, in a cluster of multihomed Web servers.

See also: host; multihomed computer; IP address

virtual local area network (VLAN)

A logical grouping of hosts on one or more LANs that allows communication to occur between hosts as if they were on the same physical LAN.

See also: host; local area network (LAN)

virtual memory

Temporary storage used by a computer to run programs that need more memory than it has. For example, programs could have access to 4 gigabytes of virtual memory on a computer's hard drive, even if the computer has only 32 megabytes of RAM. The program data that does not currently fit in the computer's memory is saved into paging files.

See also: paging file; Virtual Memory Size; virtual printer memory

Virtual Memory Size

In Task Manager, the amount of virtual memory, or address space, committed to a process.

See also: Task Manager; virtual memory

virtual printer memory

In a PostScript printer, a part of memory that stores font information. The memory in PostScript printers is divided into two areas: banded memory and virtual memory. The banded memory contains graphics and page-layout information needed to print your documents. The virtual memory contains any font information that is sent to your printer either when you print a document or when you download fonts.

See also: PostScript printer; virtual memory

virtual private network (VPN)

The extension of a private network that encompasses encapsulated, encrypted, and authenticated links across shared or public networks. VPN connections can provide remote access and routed connections to private networks over the Internet.

See also: authentication; encryption; routing; tunnel

VoIP (Voice over Internet Protocol)

A method for sending voice over a LAN, a WAN, or the Internet using TCP/IP packets.

See also: local area network (LAN); Transmission Control Protocol/Internet Protocol (TCP/IP); wide area network (WAN)


An area of storage on a hard disk. A volume is formatted by using a file system, such as FAT or NTFS, and has a drive letter assigned to it. You can view the contents of a volume by clicking its icon in Windows Explorer or in My Computer. A single hard disk can have multiple volumes, and volumes can also span multiple disks.

See also: disk; drive letter; file allocation table (FAT); NTFS file system; simple volume; spanned volume


Waiting for Call

A telephony signal that Network Connections has put the modem in Listen mode and is waiting for incoming calls.

See also: modem (modulator/demodulator)

Web Distributed Authoring and Versioning (WebDAV)

An application protocol related to HTTP 1.1 that allows clients to transparently publish and manage resources on the World Wide Web.

Web server

A computer that is maintained by a system administrator or Internet service provider (ISP) and that responds to requests from a user's browser.

See also: Internet service provider (ISP)


wide area network (WAN)

A communications network connecting geographically separated computers, printers, and other devices. A WAN allows any connected device to interact with any other on the network.

See also: device; local area network (LAN)


A portion of the screen where programs and processes can be run. You can open several windows at the same time. For example, you can open your e-mail in one window, work on a budget in a spreadsheet in another, download pictures from your digital camera in another window, and order your weekly groceries on the Web in another window. Windows can be closed, resized, moved, minimized to a button on the taskbar, or maximized to take up the whole screen.

Windows password

A password you use to log on to Windows. You can also change your settings so that you can log on to Windows without a password.

wireless communication

Communication between a computer and another computer or device without wires. The form of wireless communication provided as part of the Windows operating system uses infrared light to transmit files. Radio frequencies, as used by cellular and cordless telephones, are another form of wireless communication.

See also: infrared (IR); infrared device; infrared port


A tool that guides a user through the steps of a process or task by asking a series of questions or presenting options. For example, wizards might help you to start up a word processing document, install software, or create a database file for the first time.


A simple grouping of computers, intended only to help users find such things as printers and shared folders within that group. Workgroups in Windows do not offer the centralized user accounts and authentication offered by domains.

See also: authentication; domain; user account

World Wide Web

A system for exploring the Internet by using hyperlinks. When you use a Web browser, the Web appears as a collection of text, pictures, sounds, and digital movies.

See also: internet

writable CD

Recordable compact disc (CD-R) or rewritable compact disc (CD-RW). Data can be copied to the CD on more than one occasion. Rewritable compact discs can also be erased.


X.509v3 certificate

Version 3 of the ITU-T recommendation X.509 for certificate syntax and format. This is the standard certificate format used by Windows XP certificate-based processes.

An X.509 certificate includes the public key and information about the person or entity to whom the certificate is issued, information about the certificate, plus optional information about the certification authority (CA) issuing the certificate.

See also: certificate; certification authority (CA)


Refers to microprocessors that have or emulate the 32-bit Intel processor architecture.

XML (Extensible Markup Language)


There are no glossary terms that begin with this letter.


There are no glossary terms that begin with this letter.



To find a term in the glossary, click the letter of the alphabet that is the first letter in the term you want to look up.

You can also read glossary terms within the text of Help by clicking the underlined glossary term links. After you click a glossary link, the glossary term and definition appear in a pop-up window. To close the window, click anywhere on the screen.




The traditional format in which audio and video are transmitted by using a wave or analog signal. An analog signal may not work with digital speakers; computers use digital signals.

anchor window

A small window that can appear in the lower-right corner of the screen when Windows Media Player is in skin mode. You can use the window to return to full mode and access other commands.

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The transmission method used by a radio station (AM, FM, or Internet).


A network's capacity for transferring an amount of data in a given time.

bit rate

The number of bits transferred per second.


A transmission medium designed for high-speed data transfers over long distances. Cable modem services and DSL are examples of broadband networks.


An area of computer memory reserved for temporarily holding data before that data is used on the receiving computer. Buffering protects against the interruption of data flow.

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call sign

The identifying code letters or numbers of a radio or television transmitting station, assigned by a regulatory body.


Text that accompanies images or videos, either as a supplemental description or a transcript of spoken words.


See definition for: compact disc (CD)

CD burner

See definition for: CD recorder

CD recorder

A device used to copy files to recordable CDs.


See definition for: compact disc-recordable (CD-R)


See definition for: compact disc-rewritable (CD-RW)


In a DVD, a portion of a title, such as a scene or sequence. A title can contain one or more chapters.

See also: title


An abbreviation for compressor/decompressor. Software or hardware used to compress and decompress digital media.

compact disc (CD)

An optical storage medium for digital data.

compact disc-recordable (CD-R)

A type of CD on which files can be copied, but not erased or replaced.

compact disc-rewritable (CD-RW)

A type of CD on which files can be copied, erased, and replaced.


A process for removing redundant data from a digital media file or stream to reduce its size or the bandwidth used.

connection speed

The maximum rate, in bits per second, at which data can be transferred between a network and a computer or device.

content provider

The person or organization that distributes Windows Media files (for example, a record, movie, or streaming media company). The content provider may also be the content owner.

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To convert encrypted content back into its original form.

See also: encrypt


Data represented as binary digits (zeros and ones).


To transfer a file over a network in response to a request from the device that receives the data. Downloaded content is kept on the receiving device for playback on demand. In contrast, streamed content is played as it is delivered.

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Editing with keyboard and mouse.
a special file that will hold one item of any type. Windows uses the clipboard for Cut, Copy and Paste operations
To remove a selected item (text, a picture, whatever) from where it is and place it on the Clipboard for pasting to a new location
Usually in the Edit menu.
Keyboard Shortcut Ctrl-X
Copies the selected item to the clipboard but leaves it where it was also
Usually in the Edit menu.
Keyboard Shortcut Ctrl-C
Place a copy of the item on the clipboard where the insertion point is.
Usually in the Edit menu.
Keyboard Shortcut Ctrl-V
Undoes the last change you made. Usually in the Edit menu.
Keyboard Shortcut Ctrl-Z
Dialog Box
A small window that a program pops up to tell you or ask you something.
To press down and release the left button of a mouse. Causes some action such as selection or activation.
Double Click
To click twice in rapid succession - you know, go "click click". Activates an icon or opens a folder.
Right Click
Opens a context sensitive menu.
Press down and on the left mouse button then move the mouse. Let up on the button to finish.
Right Drag
Press down and on the right mouse button then move the mouse. Let up on the button to finish. When you let up a menu will appear.


To convert audio and video content to a specified digital format.


To programmatically disguise content to hide its substance.

See also: decrypt

error correction

In Windows Media Player, a process to ensure that digital audio data is read from the CD-ROM drive accurately during playback or copying. Using error correction can prevent undesirable noises that are not part of the original material.

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file format

The structure or organization of data in a file. File format is usually indicated by the file name extension.

See also: file name extension, file type

file name extension

A set of characters added to the end of a file name that identifies the file type or format.

See also: file format, file type

file type

A description of the content or format of a file. File type is usually indicated by the file name extension.

See also: file format, file name extension


A combination of hardware and software that enforces a boundary between two or more networks and prevents unauthorized access to a private network.


One of many sequential images that make up video.

frame rate

The number of video frames displayed per second. Higher frame rates generally produce smoother movement in the picture.


In Windows Media Player, the number, such as 88.5 or 101.7, used to locate a radio station.

full mode

The default operational state of Windows Media Player in which all of its features are displayed. The Player can also appear in skin mode.

See also: skin mode

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In Windows Media Technologies, the type of music, such as rock or classical, played by a radio station.

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See definition for: High Definition Compatible Digital (HDCD)

High Definition Compatible Digital (HDCD)

A patented encode/decode process that improves the quality of all forms of digital audio recording and playback by increasing resolution and reducing distortion that occurs during analog-to-digital (A/D) and digital-to-analog (D/A) conversion, digital processing, and digital filtering.


See definition for: Hypertext Transfer Protocol (HTTP)

Hypertext Transfer Protocol (HTTP)

The Internet protocol used to deliver information over the World Wide Web.

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licensed file

A Windows Media file that has an associated license that defines how the file can be played. The restrictions stated in the license vary depending on the license creator. When a CD track is copied by using Windows Media Player, a license can be assigned to the newly created file. Under that license, the file can only be played on the computer where the file was created.

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See definition for: multiple bit rate (MBR)

media information

Information about digital media content such as the artist, title, album, producer, and so forth. Also known as metadata or tags.


See definition for: Musical Instrument Digital Interface (MIDI)

Moving Picture Experts Group (MPEG)

The committee that creates international standards for coding audio-visual information to a digital, compressed format. The acronym MPEG is appended to the beginning of individual specifications developed by the committee. For example, MPEG-2 refers to the standard, ISO/IEC - 11172.


See definition for: Moving Picture Experts Group (MPEG)


A content delivery method in which a single stream is transmitted from a media server to multiple clients. The clients have no connection with the server. Instead, the server sends a single copy of the stream across the network to multicast-enabled routers, which replicate the data. Clients can then receive the stream by monitoring a specific multicast IP address and port.

multiple bit rate (MBR)

A characteristic of a data stream in which the same content is encoded at several different bit rates in order to optimize content delivery.

Musical Instrument Digital Interface (MIDI)

A specification of the MIDI Manufacturers Association (MMA). The specification defines a protocol for describing music data, such as note on and note off messages; a file format for storing music data, called Standard MIDI; and a standard hardware interface.

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A list of digital media content.


A connection point in a computer through which a peripheral device or another computer can communicate.

portable device

A mobile electronic device that can exchange files or other data with a computer or device. Examples of portable devices include Pocket PCs, portable digital music players, and Smartphones.


A set of formats and procedures that enable computers to exchange information.

See also: Hypertext Transfer Protocol (HTTP), Transmission Control Protocol (TCP), User Datagram Protocol (UDP)

proxy server

A server located on a network between client software, such as a Web browser, and another server. It intercepts all requests to the server to determine whether it can fulfill them itself. If not, it forwards the request to another server.

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Selected Item
The item (text, picture, icon, file, folder, whatever) that is highlighted is said to be Selected. This means the next thing you do will happen to that item.
For instance, if you highlight some text, it is selected. Then you hit the delete key or start typing, the selected text is replaced by the new text.



A user interface that provides an alternative appearance and customized functionality for software such as Windows Media Player.

skin mode

An operational state of Windows Media Player in which its user interface is displayed as a skin.

See also: full mode, skin


A method of delivering digital media across a network in a continuous flow. The digital media is played by client software as it is received. Typically, streaming makes it unnecessary for users to download a file before playing it.

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See definition for: Transmission Control Protocol (TCP)


On a DVD, typically, the largest unit of content, such as a movie or TV program, is called a title. There is not a consistent standard across all DVDs and because of this, a DVD can contain one or more titles.

See also: chapter


An individual song or other discrete piece of audio content.

Transmission Control Protocol (TCP)

The protocol within TCP/IP that governs the breakup of data messages into packets to be sent via IP, and the reassembly and verification of the complete messages from packets received by IP.

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See definition for: User Datagram Protocol (UDP)

User Datagram Protocol (UDP)

A connectionless transport protocol in the TCP/IP protocol stack that is used in cases where some packet loss is acceptable, for example, with digital media streams.

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In Windows Media Player, a graphical display that changes in response to the audio signal.

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Windows Media file

A file containing audio, video, or script data that is stored in Windows Media Format. Depending on their content and purpose, Windows Media files use a variety of file name extensions, such as: .wma, .wme, .wms, .wmv, .wmx, .wmz, or .wvx.

Windows Media Format

The format used by Microsoft Windows Media Technologies (or a third-party product that incorporates a licensed Windows Media technology) to author, store, edit, distribute, stream, or play timeline-based content.

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