Glossary of Computers

COMPILED BY :Prof. Humaira Khan

Binary Digit

Either a one (1) or a zero (0) as used in the binary number system. Also called a bit.


A binary digit.

Bit Rate

A measure of data transmission speed. Also stated in terms of bits per second (bps).

Database Management System

A software program designed to manage and manipulate a database of information. Abbreviated as DBMS.


Abbreviation for database management system.


To test a computer program and eliminate bugs, or errors in the program.

Desktop Computer

A PC that sits on a desk or work table and is not easily portable. Contrasted with portable and laptop units.

Desktop Publishing

The process of using a PC to produce high-quality printed documents, including camera-ready materials. Enables you to merge and preview text and graphics on the PC screen before printing occurs.

Digital Electronic Circuitry

Electronic signals or data storage techniques that use only two information states, on and off. PCs rely heavily on digital electronic circuitry.


A scanner that converts images or text into digital information.


An index of files on a storage device


The medium (floppy, hard, cartridge) or the hardware device that uses the medium.

Disk Cartridge

A removable disk that holds large amounts of information.

Disk Controller

A card or circuitry in the PC that controls the operations of the disk drives.

Disk Drive

A peripheral device that reads data from and writes data to disks.

Disk Operating System

The set of software programs that controls the basic operations of a Pc. On the PC, there are two common operating systems, PC-DOS and MS-DOS. Abbreviated as DOS.


A floppy disk. Often shortened to simply " disk."

Display Adapter

A board or circuitry in a PC that controls the type of display information on the monitor. The adapter converts the PC's digital signals into signals that can be understood by the monitor.

Documentation software

The printed information that comes with a PC.

DOS Shell

A program that lets a user activate DOS commands from menus or lists.

Dot Pitch

A measure of how close together the color dots are on a monitor. Expressed in millimeters; the smaller the value, the better the resolution of the monitor

Dot-matrix Printer

A printer with a print head that has a matrix of small pins. It prints characters by selecting combinations of pins and striking the print head against the paper.

Draw Program

A type of graphics program that creates final images by overlaying combinations of objects (lines, curves, solids, shapes).


Abbreviation for desktop publishing.


To alter a document or image.


An enhanced graphics adapter.

Electronic Mail

Communications that are transmitted and received by using PCs and other computers.

Enhanced Graphics Adapter

A video standard introduced to provide greater resolution and more colors than earlier PC graphics modes such as CGA. Abbreviated as EGA.

Ergonomic Features

Design features that account for the way humans think, move, and are built to allow people to use software and equip­ment more efficiently and with greater comfort.

Expansion Board

A circuit board that expands the capabilities of a PC.

Expansion Slot

A slot in the PC chassis to house an expansion board.

External Storage Devices

Any data storage device that sits outside the PC chassis.

Fatal Error

A catastrophic error that happens while you are running a software program. Also called a crash of the system.


Abbreviation for facsimile; the electronic transmission of documents.


A collection of data on a disk or other medium. Each file is identified by a filename.


The name of a file on a disk or other medium.


Software that has been converted into circuitry on a chip.

Fixed Disk

Another name for a hard disk.

Flat-bed Scanner

A type of scanner that lets you scan entire pages of information in one pass.

Floppy Disk

On a PC any of the various types of smaller, removable disks used.


A collection of characters that appears on the screen or page in one typeface.


The amount of space taken up by a PC as it sits on a flat surface.

Form Letters

Documents in which selected parts are changed by the software as the letter is printed.


A mathematical object that can be used to create interesting graphics images.


A type of user-supported software. "Freeware" is a copy-righted term owned by Headlands Press.

Friction Feed

On printers, the method of paper movement that relies on the pressure of a roller against the paper.

Function Keys

A set of keys on the keyboard that change function based on the software being used.


Approximately one billion bytes or a thousand megabytes.

Graphical User Interface

A style of software interface that lets users interact with programs visually. Referred to as a CUI (pronounced "gooey"), this type of interface relies on icons and images rather than on command-type interactions.


Images, as opposed to text and numbers.

Graphics Board

A circuit board that controls a PC's graphics capabilities.

Graphics Printer

Any printer that supports graphical output.

Graphics Tablet

A sensitized tablet that a user can draw on to create images on the PC's screen.


Abbreviation for graphical user interface.

Hard card

A hard disk that is mounted on a circuit board and fits into an expansion slot within the PC chassis.

Hard Disk

An auxiliary storage device with a fixed and usually non-removable magnetic disk component.


The printed output from a computer.


The collection of electronic devices that make up Pc. Hardware includes chips, keyboards, disk drives, the chassis, the monitor, printers, scanners, and pointing devices.


A measure of cycles per second. One hertz equals 1 cycle per second (cps).

High Resolution

A measure of sharpness and clarity of images on monitor, as contrasted with low or medium resolution units.


Abbreviation for hertz.


Abbreviation for Input/output.


Any PC that matches the features and capabilities, a standard IBM Pc.


A graphics image that represents an object, program, or feature.

Impact Printer

Any printer in which the print head strikes the paper, Ink-jet Printer A printer that directs tiny, electro statically charged in particles onto the paper. Also see Bubble-jet printer.

Integrated Circuit

A collection of interconnected electronic components, mounted on a single chip, designed to perform a set of specific functions.

Integrated Software Package

Any software package that combine one or more programs into a single system in which data files can be exchanged between program units.


The communication boundary between two dissimilar processes; for example, the interface created by a programmer between the program and the user who plans to use the package.


A pointing device used primarily with entertainment packages.


Abbreviation for kilobyte.


Any of the buttons on the surface of a keyboard.


A collection of keys mounted into a single unit. The PC keyboard is the primary input device to a PC program


Approximately 1000 bytes or characters of data. Abbreviated as KB.

Laptop Computer

A smaller, lighter-weight version of the desktop computer; which can be carried to different locations.


Describes a printer that produces output that looks as good as or better than a typewritten document. Abbreviated as LQ.

Light Pen

A pointing device that users can touch to the monitor's screen to make selections.


To bring information into the PC's memory.


Abbreviation for letter-quality.


Abbreviation for megabyte.


Abbreviation for monochrome display adapter.


Approximately 1 million bytes of data. Abbreviated as MB.


One million hertz or one million cps. Abbreviated as MHz.


That part of the PC in which information is temporarily stored until it is needed by the computer's CPU.


A set of options arranged in a list.


Abbreviation for megahertz.


Another name for a Pc.


The type of chip found inside the PC; the CPU.


One millionth of a second.


One thousandth of a second.


A device that translates digital signals from the PC into signals that can be transmitted over telephone lines. This unit also decodes incoming signals back into data that can be handled by a Pc.


The display screen of a Pc.


Abbreviation for monochrome.


Shorthand notation for a display adapter that handles only monochrome images but at VGA resolutions.

Monochrome Display Adapter

The form of PC video display that uses only two colors (white on black, white on green, and so on). Often abbreviated as MDA.

Monochrome Monitor

A monitor that displays in only two colors (white on black, white on green, etc.)


The main circuit board in a Pc, to which other components are attached.


A pointing device that rolls around on a flat surface. The movement of the mouse is translated on the screen into movements of a cursor.

Mouse Pad

A textured, rectangular pad on which you can roll a mouse.


The Microsoft disk operating system.


Describes a printer that produces output of less quality than a typewritten document. Abbreviated as NLQ.


Abbreviation for near-letter-quality.

Non-impact Printer

A printer that does not print by having a print head strikes the paper. Examples are bubble-jet and laser printers.


Abbreviation for optical character recognition.

Operating Environment

The software environment within which software programs operate. Can also refer to a DOS shell or to a GUI.

Operating System

Usually, the disk operating system (DOS). The two most common operating systems are PC-DOS and MS-DOS. Abbreviated as OS.

Paint Program

A software package that lets a user paint images on the screen with a set of paint tools (brushes, spray cans, shape-maker and textures). Paint programs let users control each pixel (dot) on the screen.

Parallel Port

A port on a PC that transmits several bits of information simultaneously.


Abbreviation for personal computer.


Another term for IBM-compatible; PCs that provide the features and functionality of the standard IBM PCs.


The disk operating system provided by IBM.

Peripheral Devices

Same as peripherals.


Any of the devices that attach to a PC (printers, keyboard, monitors, pointing devices, and external storage units).

Personal Computer

The small, powerful microcomputers also referred to as PCs.


The smallest dot on the screen of a Pc.

Point Size

The size of a character.


An outlet on a PC where a peripheral device cable can be attached.


A set of instructions that tells the PC what to do; also, the act of creating a program.


A person who writes or creates programs.

Public Domain

Software that has been created and made available, at no charge, to the general public.


Random-access memory. That part of the PC's memory in which information is stored temporarily when the PC is turned on. When the PC is turned off, data stored in RAM disappears.


The sharpness and clarity of images on a PC monitor; also, the number of dots per inch of images on a screen or on the printed page.


Read-only memory. That part of a PC's memory that permanently contains program instructions and data. The contents of ROM do not disappear when the PC is turned off.


A device that converts text and graphics on paper into files that can be used by a computer.

Serial Mouse

A mouse that connects to one of the serial ports on the Pc.

Serial Port

A port of the PC that transmits information one bit at a time.


A type of user-supported software that users get to "try before they buy." Shareware authors are supported by voluntary user registration fees paid directly to the programs' creators.

Comments and Suggestions are invited