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Technology Terminologies(A to Z)

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A set of data that defines a unit of work for a computer; it usually includes all necessary computer programs, linkages, files and instructions to the operating system.


Joint Photographic Experts Group. The ISO proposed standard for compression of digital data, especially 24-bit color images. It is lossy in that it reduces the file size at the expense of image quality. PostScript Level 2 color printers are supposed to be able to receive, decompress and print JPEG compressed images. Uses quantization and Huffman encoding.


In word processing, to print a document with even (straight, non-ragged) right and left margins.


A communications protocol that allows you to transfer files between your computer and on-line network systems. Kermit has built-in error correction and can handle binary (non-text) files.


An identifier in a database or file. A primary key is a unique identifier. A secondary key is typically not unique. A key may be used to specify data in a query. Example: Tag number to specify a car in a database of automobile registration information.


Similar to a typewriter, contains the letters for typing text, and keys that give the computer its commands.


1,024 bytes, often used to mean 1,000 bytes.


Local Area Network. A network that usually covers a contiguous and fairly small geographical area.

LAN e-mail system

An e-mail system in which the UA runs on LAN-attached workstations.


Large, metallic-looking records about the size of 33 RPM albums (12 inches in diameter), sometimes called videodiscs. Laserdiscs can store a vast amount of information in text, sound, and images. To play a laserdisc, you need a laserdisc player and either a computer monitor or television set. Laserdiscs come in two formats. CLV (constant linear velocity) is accessed by time and CAV (constant angular velocity) is accessed by frame number.

laser printer

A electrophotographic (xerographic) printer in which a laser is used as the light source.


In communications, a wire connecting a terminal to a computer; also a unit of text.

line editor

An editor where the text is considered to be a series of lines separated by end-of-line markers and in which alterations are made to individual lines or groups of lines through editor commands.

line printer

A computer output device in which an entire line of print is composed and determined within the printer prior to printing. The line is printed as a unit and there is no movement of a print head.


A form of markup which designates that data within a document will automatically connect with either nested data or an outside source. Used in the design of hypertext.


A server that manages named lists of recipients and files and access-controls for them. Accepts commands by interactive message or electronic mail. A note sent to a list name is resent to each recipient in the list. Will send a copy of a file on command.


v. To transfer a program held on some external storage medium (such as magnetic tape or disk) into the main memory of the machine in a form suitable for execution.

logical record

All the data for a given unit of analysis . It is distinguished from a physical record because it may take several physical records to store all the data for a given unit of analysis. For instance, in Card Image data, a "card" is a physical record and it usually takes several "cards" to store all the information for a single case or unit of analysis.

login or logon

The opening sequence of keystrokes used via computer screen instructions to connect to a system or begin operations on a computer.

login ID

Same as account name or user ID.


Leave a network system, usually by typing "bye" or "q" for quit. Sometimes called "logout."


Line Printer Remote. A protocol that allows one system to send a file to another system to be queued to a device to which the receiving system has access.


A text-based World-Wide Web browser. Because it does not employ a graphics capability, it allows slower computers (or computers using a modem) to access the Internet with ease.

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