COMPUTER DEFINITIONS AND TERMINOLOGIES

A

Application: A computer program designed to perform specific tasks for the user. Examples include Microsoft Word, Microsoft Excel, and web browsers.

Access Time: The time required by a storage device to locate and access a particular piece of data.

Active Program/Window: The program or window currently in the foreground and ready to receive user input.

ALGOL: ALGOL (Algorithmic Language) was developed in 1958 for scientific and mathematical computing. It introduced formal grammar concepts and influenced later programming languages such as Pascal, C, C++, and Java.

Algorithm: A step-by-step procedure or set of instructions used to solve a problem or accomplish a task. An algorithm should eventually reach a defined result.

ASCII: ASCII stands for American Standard Code for Information Interchange. It is a character-encoding standard used to represent text and symbols using numerical codes.

Amplifier: An electronic device that increases the strength of a weak electrical signal.

Analog Computer: A computer that processes continuously changing physical quantities such as temperature, pressure, speed, or voltage.

Android: A Linux-based operating system primarily designed for touchscreen mobile devices such as smartphones and tablets.

Antivirus Software: Software designed to detect, prevent, and remove computer viruses and other forms of malware.

API: API stands for Application Programming Interface. It is a set of rules and protocols that allows different software applications to communicate with each other and access specific services or functions.

Application Software: Software designed to perform specific tasks for end users, such as word processing, spreadsheet calculations, presentations, and image editing.

Archive: A file or collection of files stored for long-term storage or backup purposes.

Arithmetic Logic Unit (ALU): A component of the CPU that performs arithmetic operations such as addition, subtraction, multiplication, and division, as well as logical operations and comparisons.

Array: A collection of similar types of data elements stored in an organized sequence.

Assembler: A program that translates assembly language instructions into machine language.

Attribute: A characteristic or property of an entity. For example, the attributes of a student may include name, roll number, and age.

B

BIOS: BIOS stands for Basic Input/Output System. It is firmware stored on a computer’s motherboard that initializes hardware and helps start the booting process.

Bit: Bit stands for Binary Digit. It is the smallest unit of digital data and can have a value of either 0 or 1.

Backup: A copy of data, files, or a disk created to protect against data loss.

Backspace Key: A keyboard key that deletes the character to the left of the cursor.

Bandwidth: The maximum amount of data that can be transmitted through a communication channel in a given period of time, generally measured in bits per second (bps).

Bar Code: A machine-readable representation of information using a pattern of lines, spaces, or other symbols.

Bitmap: A method of storing a digital image as a collection of pixels represented by bits.

Blog: An online discussion or informational website published on the World Wide Web, usually containing regularly updated posts.

Logic Bomb: Malicious code designed to execute when a particular condition or event occurs, such as a specific date or time.

Bluetooth: A short-range wireless communication technology used to exchange data between nearby devices.

Booting: The process of starting a computer and loading the operating system into memory.

Boot Sequence: The sequence of operations performed by a computer when it is switched on to initialize hardware and load the operating system.

Botnet: A network of infected computers or devices controlled remotely by an attacker to perform malicious activities.

Browser/Web Browser: Software used to access, view, and navigate websites and web pages on the Internet.

Buffering: The temporary storage of data in a buffer while it is being transferred between devices or applications.

Bug: An error, flaw, or fault in a computer program that produces an incorrect or unexpected result.

Boolean: A data type or expression that can have only two possible values: True/False or 1/0.

Bus: A communication pathway consisting of wires or electronic connections used to transfer data, addresses, and control signals between computer components.

Byte: A group of 8 bits.

C

CGI: CGI stands for Common Gateway Interface. It is a standard that allows web servers to communicate with external programs or scripts.

Class: In object-oriented programming, a class is a blueprint or template that defines the properties and behaviour of objects.

Client: A computer or software program that requests services or information from another computer or program called a server.

CD-ROM: CD-ROM stands for Compact Disc Read-Only Memory. It is an optical storage medium from which data can generally only be read.

Client-Server: A network architecture in which client computers or programs request services or resources from a central server.

Clipboard: A temporary area of memory used to store data that has been cut or copied so that it can later be pasted elsewhere.

Clock Rate: The speed at which a computer’s processor performs cycles, generally measured in Hertz (Hz), MHz, or GHz.

Compiler: A program that translates an entire program written in a high-level programming language into machine code or another lower-level form before execution.

Compression: A technique used to reduce the size of a file by removing or encoding redundant data.

CPU: CPU stands for Central Processing Unit. It is the main processing component of a computer and is often called the brain of the computer.

Cache Memory: A small and very fast memory located close to or within the CPU. It stores frequently used data and instructions to reduce the time required to access the main memory.

Chip: A small piece of semiconductor material, usually silicon, containing electronic circuits.

Cookie: A small piece of data stored by a website in a user’s web browser to remember information about the user’s activity or preferences.

Communication: The transmission of data or information from one computer or device to another.

Computer Network: A group of two or more computers or devices connected to share data, resources, and services.

Computer Graphics: The creation, manipulation, and presentation of visual images, drawings, charts, diagrams, and other graphical information using a computer.

Cold Boot: Starting or restarting a computer by switching on the power after it has been completely turned off.

Control Panel: A Windows component that allows users to view and change system settings such as hardware, software, user accounts, date and time, and network settings.

Control Unit (CU): The part of the CPU that controls and coordinates the activities of other components of the computer.

Cracker: A person who gains unauthorized access to computer systems, often with the intention of stealing information or causing damage.

Crash: A failure of a computer system or program that causes it to stop functioning properly.

Cursor: A visual indicator on the screen that shows the current position where text or other input will appear.

CMOS: CMOS stands for Complementary Metal-Oxide-Semiconductor. In traditional computer systems, CMOS memory stores system configuration information such as date, time, and hardware settings. It is usually supported by a battery.

D

Data: Raw facts, figures, symbols, or information that can be processed by a computer.

DOS: DOS stands for Disk Operating System. It is a command-line operating system. MS-DOS was developed by Microsoft.

Database: An organized collection of data that can be stored, searched, managed, and retrieved electronically.

Debugging: Debugging is the critical phase in software development where programmers actively search for, identify, and resolve bugs (defects or logic errors) in their code. Defragmentation: The process of reorganizing fragmented data on a storage device so that related data is stored more efficiently.

Dialog Box: A small window that appears on the screen to request information or display options before completing a command.

Digitize: To convert analog or non-digital information into digital data.

Disk: A storage medium used to store digital data.

Disk Drive: A device used to read data from and/or write data to a storage disk.

Document: A file created using application software, such as a word-processing document.

Download: The process of receiving or transferring data from a remote computer or server to a local computer or device.

Drag: To move an object on the screen by pressing and holding a mouse button while moving the mouse.

Driver: Software that allows the operating system to communicate with and control a hardware device.

DTP: DTP stands for Desktop Publishing. It refers to software and techniques used to design and produce documents such as brochures, invitations, posters, and newsletters.

E

Editing: The process of modifying, inserting, deleting, replacing, rearranging, or formatting information.

E-mail: Electronic mail is a method of sending, receiving, and storing messages electronically over communication networks.

Encapsulation: In object-oriented programming, the process of combining data and the methods that operate on that data into a single unit and restricting direct external access.

Encryption: The process of converting readable data, called plaintext, into an encoded form, called ciphertext, to protect it from unauthorized access.

End User: The person who ultimately uses a computer system, software, or information produced by a system.

Entity: An identifiable object, person, place, or thing about which information is stored.

Entity-Relationship Diagram (ER Diagram): A diagram used to represent entities and the relationships between them in a database.

Ethernet: A widely used wired networking technology for connecting devices and transferring data over a local area network.

Execution Time: The total time taken by a computer to execute a program or instruction.

Expansion Slot: A slot on the motherboard that allows additional expansion cards to be installed to provide extra features or capabilities.

Environment: The combination of hardware, software, and network components in which a computer program operates.

F

FAT: FAT stands for File Allocation Table. It is a file system used to organize and keep track of files stored on storage devices.

Fault: A hardware or software failure that causes a system to malfunction.

Fax: Short for Facsimile, a method of electronically transmitting a copy of a document.

Field: A single category or attribute of data in a database table.

File: A collection of related data stored under a specific name.

Floppy Disk: A removable magnetic storage medium that was widely used for storing and transferring data.

Folder: A container used to organize and store files and subfolders.

Font: A particular design or style of text characters.

Fragmentation: The condition in which a file is divided into separate pieces stored in different locations on a storage device.

Freeze: A condition in which a computer or program stops responding to user commands.

Front End: The part of a software system or application that users interact with directly.

G

Gateway: A device or system that connects networks using different protocols or architectures.

Groupware: Software that enables people connected through a network to collaborate and work together on documents, projects, or databases.

H

Hardware: The physical components of a computer system that can be seen and touched, such as the keyboard, monitor, CPU, and mouse.

Hard Drive: A storage device used to store large amounts of data permanently.

Head Crash: A serious hard disk failure that occurs when the read/write head comes into contact with the surface of the disk.

High-Density Disk: A storage disk capable of storing a relatively large amount of data. A traditional high-density 3.5-inch floppy disk could store approximately 1.44 MB.

Hub: A networking device that connects multiple devices on a LAN and broadcasts incoming data to connected ports.

Hyperlink: A clickable text, image, or object that links to another web page, document, or location.

Highlight: To select text or an object so that it can be edited, copied, moved, or formatted.

Hit Rate: The percentage or fraction of memory requests that are successfully served by the cache memory.

Hz: Hertz, the unit used to measure frequency or cycles per second.

I

Icon: A small graphical symbol representing a program, file, folder, or function.

IDE: IDE stands for Integrated Development Environment. It is software that combines programming tools such as a code editor, compiler, debugger, and other development features.

Initialize: To prepare a storage device or system for use.

Insertion Point: The blinking vertical line that indicates where the next character will be entered in a document.

Installer: Software used to install a program on a computer.

Interrupt: A signal sent to the processor by hardware or software requesting immediate attention.

Instance: In object-oriented programming, an instance is an individual object created from a class.

Internet: A global network of interconnected computer networks that enables communication and the exchange of information.

J–L

Joystick: An input device consisting of a movable stick used to control movement or actions in computer applications and games.

Kernel: The central part of an operating system that manages hardware resources, system services, memory, and communication between hardware and software.

Kilobyte (KB): A unit of digital storage. In traditional computer usage, 1 KB = 1024 bytes.

Light Pen: A pen-shaped input device with a light-sensitive tip used to select or draw directly on a compatible display screen.

Loop: A sequence of instructions that is repeatedly executed until a specified condition is met.

LAN: LAN stands for Local Area Network. It connects computers and devices within a limited geographical area such as a home, office, school, or building.

Landscape: A page orientation in which the page is wider than it is tall.

Launch: To start or open a program or application.

M

Memory: The storage area of a computer used to store data, instructions, and information for processing.

Modem: Modem is derived from Modulator-Demodulator. It converts digital signals into analog signals and analog signals back into digital signals.

Morphing: The process of transforming one digital image or shape gradually into another.

Multitasking: The ability of an operating system to run or manage multiple programs or tasks apparently at the same time.

Multithreading: The ability of a program or operating system to execute multiple threads of execution within a process.

Multiuser: A system that allows multiple users to access and use computer resources.

Multiplexer: A device that selects one signal from several input signals and sends it through a single communication channel.

Menu: A list of commands or options available to the user.

Menu Bar: A horizontal bar containing menus and commands, usually located at the top of an application window.

MHz: Megahertz, equal to one million cycles per second.

N–P

Nibble: A group of 4 bits, equal to half a byte.

Network: A group of interconnected computers or devices that can communicate and share resources.

Operating System: System software that manages computer hardware and software resources and provides services for application programs.

Optical Disk: A storage medium that uses laser technology to read and/or write data.

Packet: A small unit or block of data into which messages are divided for transmission over a network.

Pixel: Pixel stands for Picture Element. It is the smallest individual element of a digital image or display.

Palette: A collection of tools, colours, or options available in a computer application.

Partition: A logical division of a physical storage device into separate sections.

Paste: To insert data from the clipboard into a new location.

PC: PC stands for Personal Computer.

PCI: PCI stands for Peripheral Component Interconnect. It is a computer bus standard used to connect expansion cards to a motherboard.

Peripheral: An external or additional hardware device connected to a computer, such as a printer, scanner, keyboard, or mouse.

Port: A physical or logical connection point used to connect devices or enable communication.

Process: A program or part of a program that is currently being executed by the computer.

Protocol: A set of rules and standards that govern communication between devices on a network.

Q–S

Query: A request for information from a database or computer system.

RAM: RAM stands for Random Access Memory. It is a temporary, volatile memory used to store data and instructions currently being processed.

Router: A networking device that forwards data packets between different networks and selects suitable paths for data transmission.

Routing: The process of selecting the best path for data to travel from one network or device to another.

Root Directory: The main or top-level directory of a storage device or file system.

ROM: ROM stands for Read-Only Memory. It is non-volatile memory that stores data and instructions permanently or semi-permanently.

Software: A collection of programs and instructions that tell a computer how to perform tasks.

Save: To store data or a file on a storage device.

Save As: To save a file with a new name, location, or format.

Scroll: To move the contents of a window up, down, left, or right to view hidden information.

Swapping: The process of temporarily moving data or programs between RAM and secondary storage.

Synchronization: The process of coordinating data or operations between two or more devices or systems.

Scroll Bar: A bar used to move through the contents of a window.

SCSI: SCSI stands for Small Computer System Interface, a standard for connecting and transferring data between computers and peripheral devices.

Serial Port: A port through which data is transmitted sequentially, one bit or series of bits at a time.

Server: A computer or program that provides data, resources, or services to other computers or programs called clients.

Shutdown: The process of safely closing programs and turning off or restarting a computer.

Spreadsheet: Application software used to organize, calculate, analyze, and present data in rows and columns.

Startup Disk: A disk or storage device containing the system files required to start a computer.

Surge Suppressor: A device designed to protect electronic equipment from sudden increases in electrical voltage.

T–Z

TCP/IP: TCP/IP stands for Transmission Control Protocol/Internet Protocol. It is the basic suite of communication protocols used on the Internet.

Title Bar: The bar at the top of a window that displays the name of the document, file, folder, or application.

URL: URL stands for Uniform Resource Locator. It is the address used to locate a resource on the Internet.

Upload: The process of sending data or files from a local computer or device to a remote computer or server.

UPS: UPS stands for Uninterruptible Power Supply. It provides temporary backup power to electronic devices during a power failure.

Virtual Memory: A memory-management technique in which a portion of secondary storage is used as an extension of RAM when the available physical memory is insufficient.

Virus: A malicious computer program that can replicate itself by inserting its code into other files or programs and may disrupt normal computer operations.

WWW: WWW stands for World Wide Web. It is a system of interlinked web pages and resources accessed through the Internet.

WAN: WAN stands for Wide Area Network. It connects computers and networks over a large geographical area.

WORM: WORM stands for Write Once, Read Many. It refers to a storage medium that can be written only once but read multiple times.

ZIP: ZIP is a file-compression format used to reduce file size and combine multiple files into a single compressed archive.

Practice Question

Debugging is
 (A) creating program code
 (B) finding and correcting errors in a program code
 (C) identifying the task to be computerised
 (D) creating an algorithm

Liaison Officer (LO) 2025

Answer: (B) finding and correcting errors in a program code

Which of the following is the smallest unit of digital data?
(A) Byte
(B) Bit
(C) Nibble
(D) Word
Answer: (B) Bit

What does ASCII stand for?
(A) American Standard Code for Information Interchange
(B) American Scientific Code for Information Interchange
(C) Automated Standard Code for Internet Information
(D) American System Code for Information
Answer: (A) American Standard Code for Information Interchange

 Which part of the CPU performs arithmetic and logical operations?
(A) Control Unit
(B) Memory Unit
(C) ALU
(D) Register
Answer: (C) ALU

 Which software translates an entire high-level language program at once?
(A) Interpreter
(B) Compiler
(C) Assembler
(D) Debugger
Answer: (B) Compiler

 Which of the following is a volatile memory?
(A) ROM
(B) RAM
(C) CD-ROM
(D) Hard Disk
Answer: (B) RAM

 What is the full form of BIOS?
(A) Basic Input Output System
(B) Binary Input Operating System
(C) Basic Internal Operating System
(D) Binary Input Output Service
Answer: (A) Basic Input Output System

 Which device connects different networks and forwards data packets?
(A) Hub
(B) Switch
(C) Router
(D) Modem
Answer: (C) Router

 What is the full form of LAN?
(A) Large Area Network
(B) Local Area Network
(C) Logical Area Network
(D) Linked Area Network
Answer: (B) Local Area Network

 Which of the following is used to access websites?
(A) Compiler
(B) Web Browser
(C) Spreadsheet
(D) Assembler
Answer: (B) Web Browser

 What is the full form of URL?
(A) Uniform Resource Locator
(B) Universal Resource Link
(C) Uniform Reference Link
(D) Universal Resource Locator
Answer: (A) Uniform Resource Locator

 Which device is used to connect multiple computers in a LAN and broadcast data to connected devices?
(A) Router
(B) Hub
(C) Modem
(D) Gateway
Answer: (B) Hub

 A group of four bits is called a:
(A) Byte
(B) Nibble
(C) Word
(D) Kilobyte
Answer: (B) Nibble

 Which of the following is an example of system software?
(A) MS Word
(B) Photoshop
(C) Operating System
(D) PowerPoint
Answer: (C) Operating System

 What is the main function of a compiler?
(A) To store data
(B) To translate a program into machine language
(C) To connect networks
(D) To scan for viruses
Answer: (B) To translate a program into machine language

 Which technology is commonly used for short-range wireless communication?
(A) Ethernet
(B) Bluetooth
(C) Fibre Optic
(D) DSL
Answer: (B) Bluetooth

 Which of the following is a file-compression format?
(A) ZIP
(B) BIOS
(C) ASCII
(D) HTML
Answer: (A) ZIP

 What is the process of transferring a file from a remote server to a local computer called?
(A) Uploading
(B) Downloading
(C) Browsing
(D) Routing
Answer: (B) Downloading

 Which device provides temporary backup power during a power failure?
(A) CPU
(B) UPS
(C) Modem
(D) Router
Answer: (B) UPS

 What is a collection of infected computers controlled remotely by an attacker called?
(A) Firewall
(B) Botnet
(C) Gateway
(D) Protocol
Answer: (B) Botnet

 Which of the following is the correct full form of TCP/IP?
(A) Transmission Control Protocol/Internet Protocol
(B) Transfer Control Program/Internet Process
(C) Transmission Communication Protocol/Internet Program
(D) Transfer Communication Protocol/Internet Protocol
Answer: (A) Transmission Control Protocol/Internet Protocol