L

laser
Originally LASER, an acronym for light amplification by stimulated emission of radiation, now a word in its own right. A device that utilizes certain quantum effects to produce coherent light in the visible, infrared or ultraviolet ranges.

laser jet
A printer type that uses a laser to form images on a surface that are transferred to a page and are printed in the same way as a copying machine prints.

laser printer
An electrophotographic printer that is based on the technology used by photocopiers.

latency
The delay time between the end of one communication and the start of another. During this time, the processes associated with the communication are hung up and cannot continue. Software engineers work to reduce latency to a minimum.

layout
The overall plan or design of a document system. In graphics, word processing and page layout programs, for example, the layout of a page refers to the size of margins and the placement of text, headings and graphics on the page.

Light Emitting Diode (LED)
A diode that converts electrical energy into light, producing relatively little heat for the amount of light output.

line
A connection between sending and receiving devices, including telephones, computers, and terminals. A line in a sense is generally a physical wire or other cable connecting two pieces of equipment, as on a network.

linearity
The tendency for changes in an image to be constant. Non-linearity causes images to be more distorted in one area of the screen than in another. This is sometimes caused by poor voltage regulation in the monitor�s electronics.

link
A transmission path between two data sets, channels or switching offices.

Linux
Version of UNIX freeware available on the Internet. Linux was developed in 1991 by Linus Torvalds.

Liquid Crystal Display (LCD)
A display (monochrome or colored) using liquid crystal technology; often used in laptops.

load
To place information from storage into memory for processing or for execution.

Local Area Network (LAN)
A network physically confined to a small region of space, typically within a single building; contrasting with a Wide Area Network (WAN), which may be country-wide or even world-wide.

local bus
A direct connection between the processor and memory producing very fast communication speeds.

lock up
A condition in which processing appears to be completely suspended and in which the program in control of the system will accept no input.

locked file
A file upon which one or more of the usual types of manipulation operation cannot be performed—typically, one that cannot be altered by additions or deletions.

log
A record of transactions or activities that take place on a computer system.

logic
In programming, the assertions, assumptions and operations that define what a given program does. Defining the logic of a program is often the first step in developing the program�s source code.

logic chip
A chip that processes information, as opposed to simply storing it.

logical address
An address referred to by its name or purpose rather than by its physical location. The logical address of a file on disk is given by its path, i.e. how it is to be located through the software structures. Contrast this with the physical address, which is a numeric code used by the operating system, but unintelligible to the human user.

logoff
The process of terminating a session with a computer accessed through a communications line—usually a computer that is both distant and open to many users. Logging off is the user�s means of telling the computer, "I�m finished; go ahead and disconnect." It is not the same as shutting down (turning off) a computer.

logon
The process of identifying oneself to a computer after connecting to it over a communications line. During a logon procedure, the computer usually requests the user�s name and a password. On a computer normally used by many people, a logon procedure provides a means of identifying authorized users, keeping track of the usage time and maintaining security by allowing access to sensitive files only to people cleared to use them.

low emission
A characteristic of a monitor that has special shielding to lower the emission of ELF (Extremely Low Frequency) and VLF (Very Low Frequency). It is usually referred to as a government safety standard, e.g. MPRII.

low resolution
In raster-oriented computer displays and printing, a term applied to a screen or an image in which text and graphics appear in relatively coarse detail. Resolution is related to the number of pixels (dots) used to create the image: The fewer pixels, the lower the resolution. In printing, low resolution is comparable to draft-quality, dot-matrix output printed at 125 dots per inch or less.