A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Abend

The termination of processing due to program abnormal ending or system fault.

Abort

Generally used to terminate a process before completion.

A-B box

A control mechanism that lets two or more computers share a single peripheral, such as a printer, a scanner, or a monitor. With an A-B box in use, the user can decide which computer is able to use the device at any one time by turning a switch.

Absolute Coding

A system of programming that uses direct addressing rather than indirect addressing to specify the location of data in the memory. Direct addressing refers to the exact location of data in a computer's memory, whereas indirect addressing determines the location of data in a computer's memory by relating its position to another point.

Absolute Pathname

A pathname in relation to the root directory.

Absolute Uniform Resource Locator (absolute URL)

The full Web address, or uniform resource locator, of a Web page. It uses a protocol such as HTTP (Hypertext Transfer Protocol), a network server name, and a file name.

Accelis

A double-reeled tape format based on the recent LTO (Linear Tape-Open) standard. Initial Accelis drives are planned to have cartridges with 25GB (gigabyte) native capacities (50GB compressed) and data transfer rates of 1.2 to 2.4GB/minute.

Access Arm

In a hard drive, the arm-like mechanism that positions the read/write head over a disk surface. The read/write head is attached to the end of the access arm.

Access Code

The user name or security code required to access a computer, a particular program, or certain files.

Access Control List (ACL)

The ACL is a list noting which users have access rights to network resources. 

Access Log 

A list of everyone (by IP Address) who visits your website, where they came from, what they do when
they’re there, what operating system and browser they use, and so on.

 In general, an access log can be analyzed to tell you:

• The number of visitors (unique first-time requests) to a home page
• The origin of the visitors in terms of their associated server's domain name (for example, visitors from .edu, .com, and .gov sites and from the online services)
• How many requests for each page at the site, which can be presented with the pages with most requests listed first
  Usage patterns in terms of time of day, day of week, and seasonally

Access Path

The complete route, including the drive letter, directory, and all subdirectories, that directs an operating system to a file or application in a storage device.

Access Permission

Different permissions associated with files to determine how they can be used. Such permissions include write, execute, and read. 

Access Point

Access point  is a device that allows wireless communication devices to connect to a wireless network using Wi-Fi, Bluetooth or related standards.

Access Rights

The rights a user or computer has to open up a communications pathway with a particular computer, component, or application. Limiting access rights keeps specific people, machines, or groups from using a certain network, machine, or files.

Access Time

The interval between a request for data from storage by the computer and the moment when it is available to the user.

Account Name

Alternate name for username or user identification

Account Policy

In multiuser networks and operating systems, the set of rules that maintains order on the network and determines user access privileges. The account policy can dictate whether an individual is granted system access and whether an approved user can be given more access.

Ack

Email shorthand for "acknowledged."

Acquire

In relation to digital imaging, acquire means to obtain a digital image from a digital camera, scanner, or other TWAIN- (Technology Without An Interesting Name) compliant device and transfer it to a computer.

Active Matrix

A type of LCD computer screen display unit that is constantly refreshing by means of transistors embedded in the screen. It is characterized by high contrast and brilliant image.

Actionscript

ActionScript is a scripting language based on ECMAScript. ActionScript is used primarily for the development of websites and software using the Adobe Flash Player platform in the form of SWF files embedded into Web pages.

Active Server Pages

Active Server Pages (ASP), also known as Classic ASP or ASP Classic, was Microsoft's first server-side script engine for dynamically-generated web pages from a database.

ActiveX

This Microsoft-based technology was built to link desktop applications to the World Wide Web. Using ActiveX development tools, software developers can create interactive Web content for their applications. For example, Word and Excel documents can be viewed directly in Web browsers that supports ActiveX.

ADCCP

An ANSI (American National Standards Institute) standard used to control data transmission among a network’s interconnected nodes.

Address bus

An electronic pathway through which the CPU specifies memory locations for the storage of data. The size of the address bus determines how many different memory locations the CPU is able to address, or use. 

Add-on

An add-on is a software extension that adds extra features to a program. It may extend certain functions within the program,  or give the program additional capabilities. For example, Internet Explorer, a popular Web browser, supports add-ons such as the Yahoo toolbar, ad blockers, and Web developer tools.

Adobe Acrobat

Adobe Acrobat is a family of computer programs developed by Adobe Systems, designed to view, create, manipulate and manage files in Adobe's Portable Document Format (PDF).

Adobe Acrobat Reader

Adobe Reader (formerly Acrobat Reader) is available as a no-charge download from Adobe's web site, and allows the viewing and printing of PDF files. Acrobat and Reader are widely used as a way to present information with a fixed layout similar to a paper publication.

Adobe Type Manager

Abbreviated ATM, a software program or system extension manufactured by Adobe Systems that is used to enhance the display of screen fonts on computer monitors, Essentially, ATM uses the outline fonts (or printer fonts) rather than bitmap fonts, which not only allows for the creation of screen fonts in any type size, but also reduces the memory and processing power needed for bitmaps. ATM is available for the Macintosh, MS-Windows, OS/2, and Unix operating systems.

ADSL

Asymmetric Digital Subscriber Line (ADSL) is one form of the Digital Subscriber Line technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice telephone call.

Adware

Adware is free software that is supported by advertisements. Common adware programs are toolbars that resides on your desktop or work in conjunction with your Web browser. They provide features like advanced searching on the Web or your hard disk drive and better organization of your bookmarks and shortcuts.

Most adware is safe to use, but some can serve as spyware, gathering information about you from your hard disk drive, the Web sites you visit, or your keystrokes. Spyware programs can then send the information over the Internet to another computer.

Affiliate

Website affiliates are what drive Internet marketing. Companies run affiliate programs to generate leads and sales from other Websites. They pay the sites who host their ads a commission for products sold through the links on their sites.

AGP

Stands for "Accelerated Graphics Port." This is a graphics card expansion port designed by Intel that resides on the motherboard of a computer.AGP ports run at 66 MHz and can transfer data up to 528 MB/sec. This allows games and applications to store and retrieve larger, more realistic 3D shapes and textures without slowing down the animation on the screen.

AIFF

Stands for "Audio Interchange File Format." AIFF is an audio format originally developed by Apple Computer for storing high-quality sampled audio data. AIFF files are similar to Windows WAVE files in both size and quality.

Algorithm

An algorithm is a set of instructions, sometimes called a procedure or a function, that is used to perform a certain task.

Alias

In computing, any shorthand an alternate name used for identification, such as for naming a field or a file abbreviated name for a file essentially a way of opening a file without typing long paths of directories through many hierarchical folders. In operating systems Alias - Typically a name, usually short and easy to remember that is translated into another name or string, usually long to remember. Most command interpreters such as UNIX operating system allows the user to define aliases for simplifying commands.

Alternate Key (Alt)

A type of control key used in conjunction with other keys to modify their actions or to execute commands.

Amplitude

The variation in a sound signal producing varying levels of loudness. Measured in decibels (dB).

Analog-to-Digital Converter (ADC)

An ADC takes an analog signal and translates it into a digital signal that a computer can understand and work with.

Analog Signals

Signals which can vary over a continuous range (e.g., the human voice over conventional telephone lines). Analog circuitry is more subject to distortion and noise, but it is more capable of handling complex signals than are digital signals which can have only discrete values.

Analog Sound

Recorded sound depicted by fluctuations in amplitude.

ANSI

American National Standards Institute. A non-profit, private industry association which governs most USA-standards setting agencies.

APF

A device used on scanners to feed photos into the scan area.

API

Stands for "Application Program Interface," though it is sometimes referred to as an "Application Programming Interface." An API is a set of commands, functions, and protocols which programmers can use when building software for a specific operating system. The API allows programmers to use predefined functions to interact with the operating system, instead of writing them from scratch.

Applet

This a Java program that can be embedded in a Web page. The difference between a standard Java application and a Java applet is that an applet can't access system resources on the local computer.

Application Binary Interface (ABI)

A specification that determines the method of storage for executable programs and defines the machine language for a specific hardware platform and operating system.

Archive

To write data to long-term storage.

ARQ

Automatic ReQuest for retransmission. A type of communications link where the receiver asks the transmitter to re-send a block of data when errors are detected.

Array

An array is a data structure that contains a group of elements. Typically these elements are all of the same data type, such as an integer or string. Arrays are commonly used in computer programs to organize data so that a related set of values can be easily sorted or searched.

ARP

Stands for "Address Resolution Protocol." ARP is a protocol used for mapping an IP address to a computer connected to a local network LAN. Since each computer has a unique physical address called a MAC address, the ARP converts the IP address to the MAC address. This ensures each computer has a unique network identification.

ASCII

Acronym for American Standard Code for Information Interchange. ASCII is an ANSI character set. The standard ASCII character set consists of 128 decimal numbers (0-127) for letters of the alphabet, numerals, punctuation marks, and common special characters. The extended ASCII character set extends to 255 characters and contains special mathematical, graphics, and foreign characters. 

ASP.NET

ASP.NET is a set of Web development tools offered by Microsoft. Programs like Visual Studio .NET and Visual Web Developer allow Web developers to create dynamic websites using a visual interface. 

Aspect Ratio

The relationship or proportion of the horizontal to vertical measurement as of a computer monitor screen or of a graphic element.

Assembler

A program that translates programs from assembly language to machine language.

Asynchronous Communications

A method of transmission in which one character is sent one bit at a time; also referred to as serial transmission.

Attenuation

The reduction of a signal’s strength without distortion as it passes through a computer system.

Audio-Visual

The term audio-visual (AV) may refer to works with both a sound and a visual component, the production or use of such works, or the equipment involved in presenting such works.