Glossary of Computer This A-to-Z glossary defines key computer engineering terms you need to know.
GLOSSARY
Access Time The time interval between the instance at which data is called from a storage device and the
instance when delivery begins.
Accumulator A local storage area called a register, in which the result of an arithmetic and logic operation is
formed.
Active Cell It refers to the currently selected cell in a spreadsheet. It can be identified by a bold outline that surrounds the cells.
Active Window It is the currently focused window in the current window manager.
Algorithm In computing, an algorithm is a procedure for accomplishing some tasks which given an initial
state, will terminate in a defined end-state.
Alphanumeric A character set that contains letters, digits and other special characters such as @, $, +, *, %, etc.
Analog Computer A computer that operates on data which is in the form of continuous variable physical quantities.
Animation It is the process of making the illusion of motion and change by means of the rapid display of a
sequence of static image that minimally differ from each other.
Antivirus It consists of computer programs that attempt to identify threat and eliminate computer viruses and
other malicious software (malware).
Application Software It is a subclass of computer software that employs the capabilities of a computer
directly to a task that the user wishes to perform.
Archive It provides backup storage.
Arithmetic Logic Unit (ALU) It is a part of the execution unit, a core component of all CPUs. ALUs
are capable of calculating the results of a wide variety of basic arithmetical and logical computations.
Artificial Intelligence Fifth generation computing devices, based on artificial intelligence, are still
in development, though there are some applications, such as voice recognition, that are being used today.
ASCII (American Standard Code for Information Interchange) It is a character set and a character encoding based on the Roman alphabet as used in Modern English and other Western European
languages.
Assembler A program that translates mnemonic statement into executable instruction.
Attribute The characteristics of an entity are called its attributes.
Authentication Any process by which a system varifies the identity of the user who wants to access it.
Auxiliary Memory It is also known as secondary memory that is not directly addressable by the CPU.
Backspace Key This key is used to delete the text. Backspace will delete the text to the left of the cursor.
Backup A copy of a file or other item of data made in case the original is lost and damaged.
Bandwidth The maximum amount of data that can travel in a communication path in a given time, measured in bits per second (bps).
Bar Code It is a machine-readable representation of information in a visual format on a surface.
Batch File It is a text file that contains a sequence of commands for a computer operating system.
Binary Coded Decimal (BCD) A coding system in which a 4 digit binary number represents each decimal digit from 0 to 9.
Bit It is the most basic information unit used in computing and information theory.
Blog It is a discussion or informational site published on the world wide web.
Bomb A type of virus designed to activate at a specific date and time on your computer.
Bluetooth It permits a wireless exchange of information between computers, cell phones and other electronic devices.
Booting It is a bootstrapping process which starts the operating system when a computer is switched ON.
Browser A special software that enables users to read/view Web pages and jump from one Web page
to another.
Buffering The process of storing data in a memory device, allowing the devices to change the data rates, perform error checking and error retransmission.
Bug It is an error, flaw, failure, or fault in a computer program or system that produces an incorrect or
unexpected result.
Bus A circuit that provides a communication path between two or more devices of a digital computer system.
Byte It is commonly used as a unit of storage measurement in computers, regardless of the type of data being stored.
Cell A box in a spreadsheet, in which you can enter a single piece of data.
Central Processing Unit (CPU) It performs the actual processing of data. The CPU is generally called by its
generic name ‘Processor’. It is also known as the brain of computer.
Channel A communication channel can be a physical link, such as a cable that connects two stations in a
network or it can consist of some electromagnetic transmission.
Chatting Typing text into a message box on a screen to engage in dialog with one or more people via the
Internet or other network.
Chip A tiny wafer of silicon containing miniature electric circuits that can store millions of bits of information.
Client-Server It is a network architecture which separates the client from the server. Each instance of
the client software can send requests to a server or application server.
Command It is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task.
Compile It is the process of converting high level languages to machine language.
Compiler It is a computer program that translates a series of instructions from high level language to machine language.
Cookie A packet of information that travels between a browser and the web server.
Communication Protocol It is a system of rules that allow two or more entities of a communications system to transmit information.
Computer Network It is a system for communication among two or more computers.
Computer Graphics These are visual presentations on a computer screen. Examples are photographs, drawings, line arts, graphs or other images.
Control Panel It is the part of Windows menu, accessible from the Start menu, which allows users to view and manipulate basic system settings and controls.
Computer Worm It is a self-replicating computer program, similar to a computer virus.
Control Unit It is the part of a CPU that directs its operation. The outputs of this unit control the activity of the rest of the device.
Crawler It is an Internet bot that systematically browse the world wide web, typically for the purpose of Web indexing. It is also called a Web spider.
Cryptography The conversion of data into a secret code for transmission over a public network.
Cut To remove an object from a document.
Data It is a collection of facts and figures which are not in directly usable form.
Database It is a collection of logically related information in an organised way so that it can be easily accessed, managed and updated.
Data Entry Direct input of data in the appropriate data fields of a database known as data entry.
Database Management System (DBMS) It is a collection of various programs. It provides a systematic way to create, retrieve, update and manage data.
Data Processing Converting data into information, is called data processing.
Data Redundancy It is a condition created within a database or data storage technology in which the same piece of data is held in two separate places.
Debugging A methodical process of finding and reducing the number of bugs, or defects are known as debugging.
Degree The number of fields associated with the database table or relation.
Desktop Publishing (DTP) It combines a personal computer, page layout software and a printer to create publications on small economic scale.
Display Unit A device with a screen that displays characters or graphics representing data in a computer memory.
Device Driver It is a computer program that enables another program, typically, an operating system to interact with a hardware device.
Dial-up Line A line through which communication established.
Digital Computer A computer that operates with numbers expressed directly as digits.
Direct Access It is the capability of the computer equipment to obtain data from a storage device.
Directory In computing, a directory is an entity in a file system which contains a group of files and other directories.
Domain Name A unique name that identifies a particular Website and represents the name of the
server where the Web pages reside.
Dots Per lnch (DPI) It is defined as the measure of the resolution of a printer, scanner or monitor. It refers to
the number of dots in one inch line.
Download It refers to the act of transmitting data from a remote computer on the Internet or other network
to one’s own computer.
Drag and Drop In computer graphical user interface, drag and drop is the action of clicking on a virtual
object and dragging it to a different location or onto another virtual object.
DVD It is an optical disc storage media format that can be used for data storage including movies with high
quality video and sound.
Dynamic RAM DRAM is a type of random access memory which stores each bit of data in a separate
capacitor.
EBCDIC (Extended Binary Coded Decimal Interchange Code) It is an 8-bit character encoding used on IBM
mainframe operating systems, like Z/OS, S/390, AS/400 and i5/OS.
E-Commerce Electronic commerce is a type of industry where buying and selling of products or services is conducted over electronic systems such as the Intranet and other computer network.
Editing The process of changing information by inserting, deleting, replacing, rearranging and reformation.
Electronic Data Processing (EDP) A data processing through equipment that is predominantly electronic
such as digital computer.
Electronic mail E-mail is a method of composing, sending, storing and receiving messages over electronic communication systems.
Encryption In cryptography, encryption is the process of encoding messages (or information) in such a way
that hackers cannot read it, but the authorised users can access it.
End User Any individual who uses the information generated by a computer based system.
Entity It is something that has certain attributes or properties which may be assigned values.
Error Message It is information displayed when an unexpected condition occurs usually on a computer or
other device.
Excel It allows users to create spreadsheets much like paper ledgers that can perform automatic calculations.
Exe (.exe) It is a common filename extension denoting an executable file (a program) in theDOS,MS-Windows.
Execution Time The total time required to execute a program on a particular system.
Expansion Slot It is a socket on the motherboard that is used to insert an expansion card which provides
additional features to a computer.
Extranet A technology that permits the users of one organisation’s Intranet to enter portions of another
organisation’s Intranet in order to conduct business transactions or collaborate on joint projects.
Fax It stands for ‘Facsimile’. It is used to transmit a copy of a document electronically.
Field The attributes of an entity are written as fields in the table representation.
File A collection of information stored electronically and treated as a unit by a computer. Every file must
have its own distinctive name.
File Allocation Table (FAT) It is the name of a computer file system architecture. The FAT file system is a legacy file system which is simple and robust.
File Manager It is an operating system utility that provides a user interface to work with file systems.
Firewall A security system usually consisting of hardware and software that prevents unauthorised persons from accessing certain parts of a program database or network.
Flowcharts These are the means of visually representing the flow of data through an information processing system, the operations performed within the system and the sequence in which they are performed.
Foreign Key A field in a database table, which links it to another related table.
Format To set margins, tabs, font or line spacing in layout of a document
FORTRAN Its name stands for formula translating system. The language was designed at IBM for scientific computing.
Freeware A form of software distribution where the author retains copyright of the software but makes the
program available to others at no cost.
File Transfer Protocol (FTP) This protocol is used to transfer files from one place to another on Internet.