thanatos106

L
Language - A systematic and formally structured means of communication instructions and data to a computer.
Laser - Acronym for Light Amplification by Stimulated Emissions of Radiation. A laser is the source of a narrow and intense beam of radiation.
Laser Printer - A printer which employs a laser beam to describe characters on paper. Normally used where high quality output is required.
LCD - Liquid-Crystal Display. A display utilizing liquid-crystal technology. It comprises two clear glass wafers, sandwiching between them a liquid crystal solution. The liquid-crystal is an organic liquid whose crystals align themselves under the influence of an electric field. Thus a measured charge can cause liquid crystals to align themselves in the form of pre-arranged alphabetic or numeric characters.
Leads - Wires used to make connections between circuits or a power source and circuit.
LED - Light Emitting Diodes. Semiconductor devices that create a low level of light; LED's have a low power consumption and long life and as such are ideal for use a display.
LIFO - Last In First Out. A method of storing data in a stack or table and retrieving first the last item stored.
Line Printer - A computer output device in which characters are printed in a horizontal line before the paper carriage moves the paper up to begin printing the next line.
Linker - The software forming part of the operating system which combines together all subroutines, programs and routines from library, utilities and so on to form a single cohesive program for a specific task.
Log - All data pertinent to a minute by minute diary of a system's activity.
Logic - The mathematical treatment of formal logic in which a system of symbols is used to represent quantities and relationships.
Looping - A repetition of instructions until a final condition is determined.
Low Level Language - A programming language that is very close to the way that the computer actually works. The use of low level languages generally ensures a more efficient use of memory that with the higher level languages but also requires a more skilled or highly trained programmer.



M
Machine Cycle - The minimum length of time in which a repetitive operation may be performed.
Machine Language - A binary code, the only language that is understood by a computer.
Macro - A group of program instructions used for a fixed, repetitive purpose. It has less function than a subroutine but is more powerful than a single instruction.
Magnetic Disk - Circular platters coated with magnetic material to facilitate data recording.
Mainframe Computer - The generic term given to the earliest computers produced by IBM and other large manufactures. Initially punch card input machines they all required extensive and sophisticated operating systems to enable economic use. The term has now lost its meaning since the advent of minicomputers.
Mega (M) - Meaning times 1,000,000 as in megabit or megabyte. To be accurate the term means 1,048,576 in binary terms.
Microcomputer - Is a collection of devices that includes a microprocessor, memory and associated interface circuits to communicate with peripheral devices or other circuits.
Microprocessor - The central processing unit fabricated on a chip. It comprises, in general, an arithmetic and logic unit, control block and register array.
Microwave - An electromagnetic wave which covers the frequencies between EHF (Extremely High Frequency) and VHF (Very High Frequency). Used for high speed data transmissions.
MIPS - Millions of instructions per second.
Modem - An acronym derived from Modulation/Demodulation device. It enables computers or peripherals to communicate via telephone lines or special dedicated data lines, by translating binary data signals to voice signals which can be carried over a telephone line and then retranslating them to data signals at the other end of the line.
Monitor - A commonly used term for the Cathode Ray Tube (CRT).
Multiplexing - A process of transmitting more than one signal at a time over a single channel.
Multiprocessing - The act of processing a number of programs or subroutines at the same time.



N
Nano (n) - Meaning divided by 1,000,000,000 (1/1,000,000,000th).
Network - A term meaning an interconnecting series of processors, channels and peripheral devices.
Node - One term for the terminal of any branch of a network having more than one branch.
Noise - Interference; electrical, acoustic or mechanical.
Non-Volatile Memory - A memory which retains its contents even after power has been discontinued. Does not normally apply to semiconductor memory, fusible links and magnetic memories are non-volatile types.



O
OCR - Optical Character Recognition, or Optical Character Reader. A device which converts special typefaces into digital signals when scanned by the reading head.
OEM - Original Equipment Manufacturer. A loosely applied term. It was originally applied to the major computer manufacturers. It is now increasingly being used to describe a company buying equipment, often from several different sources, assembling them into a unique configuration or with a unique function and then selling it on to a user, agent or distributor. The term now implies that the company adopting the description of OEM adds value to equipment before reselling it.
Ohms - A measure of the resistance or individual resistances in a circuit when the current flow is direct (DC).
Output - The results of a computer program in the form of any of the normally used computer media.



P
Pack - The process of combining data together into one location in order to save memory and speed up processing.
Page - A segment or block of contiguous memory which can be addressed by special means or by a specific field containing a complete address value.
Parallel Run - Two different systems operated simultaneously in order to verify results.
Parameter - Constant or known values or functions having variable values.
Patch - A small modification to a computer program is often known as a patch.
Peripheral - A device in a system which is not part of the central computer but is used for input or output purposes.
Plotter - A full graphics (line drawing) plotter or graph plotter, converts analog signals from the computer into a graphical form on a special purpose printer.
Poll - The process of a computer scanning each device connected to it in sequence to discover whether any data is waiting to be loaded or whether any messages requires a response.
Port - Terminals which provide electrical access to or from a system or circuit.
Power Supply - A source of electric power, either AC or DC, which is appropriate to a given circuit or system.
Power Transformer - A device for stepping down voltage to a lower more precise value.
Processor - Either the actual hardware of the central processing unit or a language designed for a very specific problem.
Program - Assembly of instructions which instruct the processor to perform a particular function.
Programmer - The computer professional who codes problems into the appropriate computer language.
Protocol - An agreed set of rules.



Q
Quality Control (QC) - The application of inspection principles to determine acceptability.
Quantum (quantum jump) - Commonly used to denote a dramatic increase in an arithmetic value.
Quartz - The crystal used in oscillators, silicon dioxide.
Queue - A stream of data, or mix of data and programs awaiting process.



R
Rack - A standard, basic metal enclosure to enable printer circuit boards to be directly mounted into one of a series of slots.
RAM - Random Access Memory. A memory consisting of a variable number of RAM chips providing access to any storage location point by means of horizontal and vertical co-ordinates. Information may be written into or taken from RAM very rapidly, under computer control. RAM may be dynamic, i.e. the contents may have to be regularly refreshed, or it may be static in which case the storage cell is a flip-flop element, in one or two stable and electrically alterable states.
Real Time Clock - The timer device that enables a real time operating system to time and share operations rapidly and accurately. It is also used to provide normal time of day functions to "time and date stamp" reports.
Redundancy - Information in a system or signals in a circuit that are transmitted for verification purposes and are not critical to the function of the system.
Refresh - The process of rewriting data in memory or on a Cathode Ray Tube where data has to be dynamically restored or regenerated.
Register - Memory on a much smaller scale than RAM or ROM. It is used by the computer to store on a temporary basis, arithmetic, logic or transferal operations.
Remote - Any location at which a peripheral or user may wish to use a system to which it is not directly connected by cable.
ROM - Read Only Memory. A device containing information which cannot be changed under computer operations. It can only be read by a computer.
Routine - A small program. Can be used by many different programs. Written and stored separately, it can be called or nested into other programs on command.
RS232C - An international standard governing the transmittal of data or signals over cables. It applies to serial transmission, i.e. one bit at a time.
Run-Time - The time taken by a discrete object program to complete its execution.