Tech Terms A-B

ABI/Inform
A database of articles in more than 800 business-related periodicals and specialty publications since 1986.


Access Provider
The company that provides you with Internet access and, in some cases, an online account on their computer system.


Acoustic Coupler 
A type of modem which converts digital signals into sound for transmission through telephone lines, and performs the reverse operation when receiving such signals. Acoustic couplers generally have cups for the telephone handset.


Active Window 
The top or front window in a multiple window environment.


A/D Converter 
A device used to convert analog data to digital data. Analog data is continuously variable, while digital data contains discrete steps.


Additive Primaries
Red, green, and blue are the primary colors of light from which all other colors can be made.


Address Resolution 
Conversion of an IP Address to the corresponding low-level physical address.


AIX 
Advanced Interactive Executive - IBM's version of Unix.


Aliasing
Visibly jagged steps along angled or object edges, due to sharp tonal contrasts between pixels.


Analog
Continuously variable signals or data.


Anonymous Login Convention (FTP)
Standard username (anonymous) and password (guest) which allows login within FTP for the purpose of retrieving an unprotected file.


ANSI 
American National Standards Institute. This organization is responsible for approving U.S. standards in many areas, including computers and communications. Standards approved by this organization are often called ANSI standards (e.g., ANSI C is the version of the C language approved by ANSI).


Application 
Software that lets users do relatively complex tasks, as well as create and modify documents. Common application types include word processors, spreadsheets, database managers, and presentation graphics programs.


ARA 
AppleTalk Remote Access. A protocol (and product) that provides system-level support for dial-in (modem) connections to an AppleTalk network. With ARA, you can call your desktop Mac from a PowerBook and remotely access all the available services - files, printers, servers, e-mail, etc.


Archie 
An information system offering an electronic directory service for locating information in the Internet that is automatically updated. The best known use of archie is for scanning a database of the contents of more than 1000 Anonymous FTP sites around the world with more than 2,100,000 file names.


ARP 
Address Resolution Protocol. Used to dynamically discover the low-level physical network hardware address that corresponds to the high level IP Address for a given host, for instance. ARP is limited to physical network systems that support broadcast packets that can be heard by all hosts on the network. A pioneering long-haul network funded by ARPA, an agency of the U.S. Department of Defense responsible for the development of new technology for the military. It served as the basis for early networking research   as well as a central backbone during the development of the Internet. The ARPANET consisted of individual packet switching computers interconnected by leased lines.


ASCII
American (National) Standard Code for Information Interchange. A standard character-to-number               encoding widely used in the computer industry.


Associate 
 Linking a document with the program that created it so that both can be opened with a single command.


AV
Audio-Visual. AV Macintosh models have video-capture hardware and have sophisticated sound (and video) recording capabilities.


AU sounds
A type of audio format used in the World Wide Web.

B

Byte. One character of information, usually eight bits wide.

Backbone

Network used to interconnect several networks together.

Backup file 

In Windows 95, a compressed version of the original file and its locations created by Backup.

Bandwidth 

The capacity of the transmission medium stated in bits per second or as a frequency. The bandwidth of optical fiber is in the gigabit or billion bits per second range, while ethernet coaxial cable is in the megabit or million bits per second range.

Baseband System

A baseband system transmits signals without converting them to another frequency and is characterized by its support of one frequency of signals. Ethernet-based networks inside campus buildings are transmitted via baseband coaxial cable, with ethernet being the only service supported by the coaxial cable.

BAT 

Filename extension for a batch file.

Batch Scanning

Sequential scanning of multiple originals using previously defined, unique settings for each.

Baud 

A unit of measurement that denotes the number of bits that can be transmitted per second. For example, if a modem is rated at 9600 baud it is capable of transmitting data at a rate of 9600 bits per second. The term was derived from the name of J.M.E. Baudot, a French pioneer in the field of printing telegraphy.

BBS 

Bulletin Board Service. A non commercial dial-up service usually run by a user group or software company. By dialing up a BBS with your modem, you can exchange messages with other users, and upload or download software.

BGI 

Binary Gateway Interface. Provides a method of running a program from a Web server. Similar to a Common Gateway Interface (CGI). The BGI uses a binary DLL which is loaded into memory when the server starts. While more efficient han a CGI, the BGI must be compiled and is not easily portable to other environments.

Bilevel

A type of image containing only black and white pixels.

Binary 

A numbering system with only two values: 0 (zero) and 1 (one).

Binary File 

A file that contains more than plain text (i.e., photos, sounds, spreadsheet, etc.) In contrast to an ASCII file which only contains plain text.

Binary Number System

A counting system used in computers consisting of only 1's and 0's (zeros).

BinHex 

A file conversion format that converts binary files to ASCII test files.

BIOS 

Basic Input-Output System. Part of the computer's operating system that is built into the machine, rather than read from a disk drive at startup.

bit 

A unit of measurement that represents one figure or character of data. A bit is the smallest unit of storage in a computer. Since computers actually read 0s and 1s, each is measured as a bit. The letter A consists of 8 bits which amounts to one byte. Bits are often used to measure the capability of a microprocessor to process data, such as 16-bit or 32-bit.

Bit Depth

The number of bits used to represent each pixel in an image, determining its color or tonal range.

Bit-map 

Generally used to describe an illustration or font file as being created by a predefined number of pixels. Also see Object-oriented.

BITNET 

An academic computer network that provides interactive electronic mail and file transfer services, using a store-and-forward protocol, based on IBM Network Job Entry protocols. BITNET-II encapsulates the BITNET protocol within IP packets and depends on the Internet to route them. There are three main constituents of the network: BITNET in the United States and Mexico, NETNORTH in Canada, and EARN in Europe. There are also AsiaNet, in Japan, and connections in South America. See CREN.

Black Point

A movable reference point that defines the darkest area in an image, causing all other areas to be adjusted accordingly.

Booting 

Starting up a computer via the power switch, which loads the system software into memory. Restarting the computer via a keystroke combination is called rebooting or a warm boot.

Bridge 

A dedicated computer used to connect two different networks. It uses data link layer address (i.e., ethernet physical addresses) to determine if packets should be passed between the networks.

Broadband System 

A broadband system is capable of transmitting many different signals at the same time without interfering with one another. For local area networks, a broadband system is one that handles multiple channels of local area network signals distributed over Cable Television (CATV) hardware.

Broadcast 

A packet whose special address results in its being heard by all hosts on a computer network.

Browser 

A program that enables you to access information on the Internet through the World Wide Web.

bps 

Bits Per Second is the unit used for measuring line speed, the number of information units transmitted per second.

BSD 

Berkeley Software Distribution. Implementation of the UNIX operating system and its utilities developed and distributed by the University of California at Berkeley. BSD is usually preceded by the version number of the distribution, e.g., 4.3 BSD is version 4.3 of the Berkeley UNIX distribution. Many Internet hosts run BSD software, and it is the ancestor of many commercial UNIX implementations.

Bug 

A mistake, or unexpected occurrence, in a piece of software or in a piece of hardware.

Byte 

The amount of memory needed to store one character such as a letter or a number. Equal to 8 bits of digital information. The standard measurement unit of a file size.