Accelerator Card

A method of speeding up an old PC by replacing the existing processor chip with a special add-in card that has a newer, faster processor.

Accelerator Key

A combination of keys that, when pressed together, carry out a task that you would have to select from a menu using a mouse. For example, instead of selecting the File menu then the Save option, many programs let you use the accelerator keys Alt and S to do the same thing and save the file.


Your subscription to a networked computer system.

Account name

Same as your login ID or user ID. The word you type at the "Login:" prompt; your electronic name.

Acoustic Coupler

A type of modem that has that has rubber cups that fit on the mouth and ear-piece of a normal phone. This converts data from the PC into sound that is then transmitted across the phone network to another computer with a modem. Most modems plug directly into a telephone socket and provide better quality sound, which means that they are more reliable. An Acoustic Coupler sends data more slowly than a modem. But it is useful if you are travelling and need to use public or hotel telephones to send data .

Active Window

The section of a screen that is currently being used. In Microsoft Windows, the active window is in front of any other window and has its title bar (at the top of the window) coloured blue. Windows which are displayed but which are not active have a white title bar.

Adapter, adapter card

Card that plugs into an expansion bus in a PC and adds a new function to the computer, or allows it to communicate with another device. For example, a sound card is a type of adapter cardthat plugs into an expansion connector and allows sound to be played back or recorded.


Like a postal address, a "network address" is used to locate another user for the purpose of directing mail. On the Internet this is in the form: account@host.domain.


The part of a system that performs information preparation and exchange on behalf of an application.


A method or procedure that solves a particular problem or performs some desired task. Programmers write instructions to implement particular algorithms in their programs. The choice of algorithm affects the performance, memory requirements and so forth.


A type of nickname (usually short and easy to remember) that refers to a type of network resource. Aliases are used so you won't have to remember the long and difficult names typical of network resources.


To line up text so that either the left or right-hand margin is level. If text is left-aligned, all the characters line up on the left-hand side, but don't on the right-hand side. If text is justified then the text lines up on the left-and right-hand edges.

Alt Key

A key on a PCs Keyboard used to activate special functions in an program. The Alt key has become the standard method of bringing up the menu bar in any software running on a PC. For example, Alt-F normally displays the File menu of a program, Alt-X normally exits the program.


A method of storing information, used by most audiotapes, videotapes and laserdiscs. An analog device uses a physical quantity, such as length or voltage, to represent the value of a number. By contrast, digital storage relies on a coding system of numeric units.

Anonymous FTP

By using the word "anonymous" as your user ID and your email address as the password when you login to an FTP site, you can bypass local security checks and gain limited access to public files on the remote computer. This type of access is available on most FTP sites, but not all.


A technique used to reduce the jagged edge that appear when circles or curves are displayed or printed out. Anti-aliasing fills this gap with a shade of the colour so the eye blends these together to give the impression of a smooth curve.


Sometimes known as a client or an "app" it's a program that performs a specific function. FTP, Mail, Gopher, Mosaic, and Telnet clients are the most common examples of Internet applications.


You'll usually hear this term referred to in the phrase archie search. Archie is a way of automatically gathering, indexing and sometimes even retrieving files on the Internet. Most good archie clients are able to FTP files once you've found the information you're looking for.


A collection of files stored on an Internet machine. FTP sites are known as archives.


Stands for American Standard Code for Information Inter-change and is pronounced as key.This is a numerical code used to represent characters. For example A is 65 and B is 66. ASCII is used by almost all computers, software and comms system, allowing different computers to exchange data. ASCII is not completely standardised. The first 128 characters are well defined and normally adhered to and cover letters, numbers and simple controls such as Delete. The characters between 128 and the limit of ASCII,255, are far from standard .

Asynchronous Transfer Mode

A transfer method that dynamically allocates bandwidth using a fixed-size packet, or cell. Also known as fast packet.

Audio File

A file that contains digital sample data from a sound. In Windows, audio files normally have a .WAV extension and are played back or recorded using the Sound Recorder utility in the Accessories group .

Audio/video interleaved (AVI)

Standard that describes how video frames and simultaneous sound should be stored in a single file. In a PC, these files have an .AVI extension and can be played back using the Media Player utility in the Accessories group.


Any process that ensures that users are who they say they are. When you type your name and password, you are authenticated and allowed access.