Glossary of Computer Terms—L

Glossary of Computer Terms—L

L

LANDSCAPE: A printer feature, generally controlled by software, which rotates the output image by 90º to print across the length rather than the width of the paper.

LAPTOP AND NOTEBOOK: Small, lightweight, portable battery-powered computers that can fit onto your lap. They each have a thin, flat, liquid crystal display screen.

LASER (LIGHT AMPLIFICATION by STIMULATED EMISSION of RADIATION): A system that generates high-intensity, highly-focused light for many purposes, including printers, high-density memory media, and a light generator for fiber optic transmission systems.

LASER DISK: See CD-ROM

LASER PRINTER: A computer-driven photocopier that creates an original image of the text or graphics from the output of the computer. A computercontrolled laser beam “paints” the desired image inside the photocopier and then prints the image on a sheet of paper.

LAST-IN, FIRST-OUT (LIFO): A method of storing and retrieving data in a stack, table, or list.

LEASED LINE: A leased phone line that provides a full-time, dedicated, direct connection to the Internet.

LIBRARY: A collection of standard software instructions, programs, routines, and subroutines in a computer’s memory.

LIGHT PEN: A light-sensitive stylus for forming graphics by touching coordinates on a display screen, thereby seeming to draw directly on the screen.

LINK: See hyperlink.

LINKAGE: Instructions that connect one program to another, providing continuity of executions between the programs.

LINUX: A UNIX like, open-source operating system developed primarily by Linus Torvalds. Linux is free and runs on many platforms, including both PCs and Macintoshes.

LIST SERVE: An Internet application that automatically “serves” mailing lists by sending electronic newsletters to a stored database of Internet user addresses. Users can handle their own subscribe/unsubscribe actions without requiring anyone at the server location to personally handle the transaction.

LIVE SCRIPT: This is the former name of Java Script. There are few updates between the two.

LOCAL AREA NETWORK (LAN): A combined hardware/software technique for interconnecting company related multiple computers or computer terminals through a high-speed networking system.

LOGIC GATE: A digital circuit resulting in an output whose state (0 or 1) depends on the specific combination of the states of input signals. Definitions of the more commonly used logic gates are listed below:

      AND: All inputs must be in a “1” state to produce a “1” state output.

      NAND (NOT AND): All inputs must be in a “1” state to produce a “0” state output.

      NOR (NOT OR): Any one input, or more, in a “1” state will produce a “0” state output.

      NOT (INVERTER): A logic gate having only one input and one output. If the input is in a “1” state, the output is in a “0” state and vice versa.

      OR: Any one input, or more, in a “1” state will produce a “1” state at the output.

      XOR (EXCLUSIVE OR): If any of the inputs are in a “1” state, but not if two or more inputs are “1”, the output is in a “1” state.

LOOK AHEAD: 1. A feature of a CPU which allows the masking of an interrupt request until the current sequential instruction has been completed.

      2. A feature of an adder circuit in the ALU section which allows the circuit to look ahead to see that all the generated arithmetic carrys are available for addition.

LOOPING: The repetition of program instructions until a conditional exit situation is encountered.

LOGIN: To attach to a computer. It has also come to represent your User ID command. 
LOGIN SCRIPT: This is the small text file that is run by the server gateway to make the attachment between it and your computer.