Computer Awareness for Competitive Exams | Glossary

Computer Awareness for Competitive Exams | Glossary

Important Terms and Glossary

A
Access Bus : It is a a new standard intended to connect relatively low-speed devices such as keyboards, mice, modems and printers. It runs on a thin four-wire cable that resembles the one that currently connects the key¬board or mouse to your computer. It also supports hot plugging i.e., one can disconnect peripherals and plug them in without letting computer shut down or reconfigure the system.
Access time : The time interval between the instant at which data is called from a storage device and the instant delivery begins.
Account: A form of access to a computer or network with specified user name and password.
Accumulator : A local storage area called a register, in which the result of an arithmetic or logic operation is formed. It is a register in which one operand of an operation can be stored and subsequently replaced by the result of that operation.
ACK : Acknowledgement from a computer that a packet of data has been received and verified.
Acoustic coupler : A communications device (modem) which allows an ordinary telephone to be used with a computer device for data transmission.
Ada : A high level programming’ language named after Ada Augusta, coworker with Charles Babbage.
Adder : A logic circuit capable of forming the sum of two or more quantities.
Address: Identification in the form of a name/ label/ number used for designating particular location in storage area.
Address register : A local storage register in the CPU which contains the address of the next instruction to be executed.
ALGOL (AlGOrithmic Language): An algebraic high-level language.
Algorithm : A sequence of precise and unambiguous instructions for solving a problem in a finite number of operations.
Alphanumeric : A character set that contains letters, digits, and other special characters such as $,@,+,*,% etc.
ALU (Arithmetic Logic Unit) : One of the components of central processing unit (CPU) of the computer that performs mathematical and logical operations.
Analog computer : A computer that operates on data: which is in-£Ke form of continuously variable physical quantities. –
Anonymous FTP : The Internet file transfer protocol. EFT sites that allow anonymous FTP do not require a password or access. One has only to log in as anonymous and enter his E-mail address as a password.
ANSI (American National Standards Lrtsfitute); A.USA based.national organization that establishes uniform standards in several fields of computers.
APL : A high level language for specifying complex algorithms. It is a real-time language primarily for scientific applications.
Application program : Software designed for a specified purpose application.
Architecture : The overall design, construction, organization and interconnecting of the various components of a computer system. Archive: Backup storage.
Arithmetic operator: A programming instruction or statement that initiates arithmetic calculation by a computer.
Artificial intelligence (AI) : A branch of computer science that deals with computers that possess reasoning, learning and thinking capabilities that resemble those of human beings.
ASCII (American Standard Code for Information Interchange) : A standard coding system for computers. ASCIl-7 is a 7-bit code and its extended version ASCII-8 is an 8-bit code.
ASCII File : It is a document file in the universally recognized text format called ASCII (American Standard Code for Information Interchange).
Assembler: A program that translates mnemonic statements into executable instructions. An assembler translates the programs written in the mnemonic assembler language into executable form.
Assembly language : A low-level programming language in which mnemonics are used to code operations and alphanumeric symbols are used for addresses. This language lies between high-level language and machine language.
Asynchronous communication: Communication between independently operating units.
Audio response: An output medium that produces verbal responses from the computer system..
Autoexec.BAT file : A special-purpose batch file (set of commands) that is automatically carried out by the MS-DOS operating system whenever the computer is started or restarted.
Automated Office : Refers to the merger of computers, office and telecommunications technology in an office environment.
Auxiliary storage: Often referred to as secondary storage. Here computer’s memory is characterized by low cost per bit stored also it has an operating speed far slower than that of the primary storage.

B
Background processing: The automatic execution of lower-priority (background) computer programs when higher- priority (foreground) programs are not using the system resources.
Backup : Alternate facilities of programs, data files, hardware equipments, etc. used in case the original one is destroyed, lost, or fail to operate.
Backup files: These are the files which are generated automatically in when one save a document. These files help in protecting the document due to out of order of the computer or power failure.
Bandwidth: The range of frequencies available for data transmission. The wider the bandwidth of a communications system the more data it can transmit in a given period of time.
Bar Code: A coding structure in which characters are represented by means of a series of parallel bars.
Base: The total number of digits (symbols) available to represent numbers in a positional number system. Baseband System : A networking system in which the channel support, a single digital signal.
BASIC (Beginners All-Purpose Symbolic Instruction Code): A high-level interactive programming language frequently used with personal computers and in timesharing environment.
Batch processing : Running of several computer programs one after another without human interaction to run each program individually. This is also known as stacked job processing because several jobs are stacked together and processed in group (batches) for efficient operation.
Baud : A unit for measuring data transmission speed that describes the capacity of a carrier. Baud is identical to bits per second.
BCD (Binary Coded Decimal): One of the early coding systems used by computers which is based on the idea of converting each digit of a decimal number into its binary equivalent rather than converting the entire decimal value into a pure binary form.
Benchmark: In the electronic information disciplines, it is as an established performane ‘ standard for processing data, aligned with which new equipment and/or software can be evaluated.
Beta Test: A process of trying out a new product by independent users before it was finally manufactured/ developed.”
Binary: A selection, choice, or condition involving two possibilities.
Binaries newsgroup: A Usenet newsgroup dedicated to the posting of unary-coded binary files, often .gif or .jpg image files.
Binary number system: A number system with a base of two. It consists of two digits 0 and 1.
BIOS (Basic Input Output System): It is responsible for handling the particulars of input/output operations.
BISYNC (binary synchronous): A process of transmitting data. It is a half-duplex, character-oriented, synchronous data communications transmission method.
Bit (binary digit): It stands for one binary piece of information which can be either 0 or 1.
BLOB (Binary Large Object): A long bit string representing complex data.
Block: A group of related items / section of program coding treated as a unit.
Block move : An operation in which data is moved to a different location.
Blocking factor: The number of logical records in a physical record..
Boolean algebra : An algebra that deals with logical propositions which are either true or false.
Boolean function : A mathematical function in Boolean algebra.
Boolean variable : A variable used in Boolean algebra. It assumes a value that is true or false.
Boot (bootstrap): The initial loading of an operating system/ programs into a computer.
Bootstrap: A small program that is invoked to draw larger and more comprehensive programs into a computer. Branch statement: An instruction that transfers program control to one or more possible paths.
Broadband channel: The fastest carriers where data transfer rates is of 1 million baud (bits/second) or more. Broadband system : A network system where several analog signals share the same physical network channel.
Bubble Memory: A compact data storage device made of thin wafers of garnet (a semiconductor material) in a magnetic field. Bubble memory devices are nonvolatile i.e., data contained in them is not lost when the power turned off.
Buffer : A device/ storage area where data are temporarily stored.
Bug : An error in a computer program..
Bulletin Board System (BBS) : A computer-based electronic mail/message system that provides a common forum for users to check/post messages, actively exchange ideas and participate in ongoing discussions.
Bus : Circuits that provide a communication path between two or more devices of a digital computer system.
Bus Topology : A network geometric arrangement in which a single connecting line is shared by a number of nodes.
Byte : A fixed number of adjacent bits that represent a particular character or symbol. Usually a byte consists of eight bits.

C
Cache memory: A small buffer storage, smaller and faster than main storage (habitually made of Static RAM). Jt is used to hold a copy of instructions and data in main storage that are likely to be needed next by the processor and that have been obtained automatically form main storage such as hard disk. It increases the speed of processing by making current programs and data available to the CPU at a rapid rate
CAD (Computer Aided Design): Utilize of computers in automate design operations.
CAI/CAE (Computer Aided Instruction/ Education): Teaching with the help of computer.
Call statement: A program statement which transfers program control to a subroutine.
CAM (Computer Aided Manufacturing): Utilizing computers in automate manufacturing operations.
Canned Programs : Programs developed by an outside supplier and provided to the user in a machine readable form.
Canonical form : A Boolean function whose terms contain all variables (or their complements). This is the unreduced form of the Boolean function’in min/max form.
Carrier : A device that is used to transmit data from one location to another.
Cartridge : A device used to contain a prerecorded program.
Cassette tape : A secondary storage medium used to store serial and sequential files.
Chain printer: A printer in which the characters are embossed on a chain or a band. The chain is in the form of a loop that rotates at a high speed and print heads are activated to print specified characters.
Channel: (i) A pathway through which information can be transmitted, (ii) Track on a magnetic tape or a band on a magnetic drum.
Character addressable storage : A storage device in which each character has one unique location with its own address.
Character printer: A printer with a print mechanism that prints one character at a time.
Charge-coupled device (CCD): An electronic storage device fabricated on semiconductor chips that stores data as packets of charge in a semiconductor.
Chip: A thin wafer of silicon on which integrated electronic components are deposited.
Circuit switching: The method of data communication in which a dedicated physical path is established between __ sender and the receiver through nodes of a network for the complete duration of information exchange.
Client/Server architecture : A configuration of computers on a network such that computing tasks are done on server computer and used by client customers.
‘COBOL (Common Business Oriented Language): A high-level programming language developed for business data processing applications.
CODASYL( Conference On DAta SYstems ?; – Various programming languages.
Code: A set of rules outlining the way in which data maybe represented/ converting data from one representation.
Coding: The process of writing computer instructions in a programming language.
Collate: To combine items from two or more sequenced files into a single one.
Collating sequence: An ordering assigned to the characters of a character set to be used for sequence purposes. COM (Computer Output Microfilm): An output device that records computer output on microfilm.
Combinational circuit: A group of logic gates interconnected to form a logic circuit.
Comment: An entry in a computer program for the purpose of documentation or explanation.
Communications channel: A medium through which data (in the form of electrical signals) is transferred from one location to another.
Communications processor: A processing unit that coordinates networks and data communications. In a computer network it ensures that data flows to/ from, different computer systems correctly and efficiently.
Communications protocol: A set of rules and procedures established to interconnect different computers and communicate between them.
Communications satellite: Microwave relay stations precisely rotate above earth with an orbit speed that exactly matches the earth’s rotation speed. Used for data transmission between any two randomly chosen points in a very large area.
Compile: To convert or translate a program written in a high-level language to an absr lule or machine language fonn.
Compiler: A system software package that converts a high-level language program to machine language.
Computer: An electronic device designed to automatically accept and store input data, process them and prod Lice output results under the direction,of a detailed step-by-step stored program or instructions.
Computer graphics : The area of computer science which is concerned with the generation, manipulation and display of pictures with the aid of a computer.
Computer network: A distributed data processing system in which multiple computers are linked together for the purpose of data communication and resource sharing.
Computer operator: A person in the computer center whose duties include setting up the processor and peripheral equipments, starting the program, run/checking on processor operation and unloading equipments at the end of a run.
Computer system : The various components (input and output devices, storage,CPU) of a computer integrated together to perform the steps called for in the program being executed.
Conditional transfer: An instruction that may cause a departure from the sequence of instructions being followed, depending upon the result of an operation.
CONFIG.SYS: A special text file that controls certain aspects of operating system behaviour.
Connector symbol: Used in a flowchart to represent a junction in a flow line, this symbol is often used to transfer flow between different pages of a lengthy chart.
Console: The part of a computer system that enables human operators to communicate with the computer. Constant: A value written into a program instruction that does not change during the execution of the program.
Contention: The method a network uses to determine access to a channel when two or more nodes wish to use it at the same time.
Control program: An operating system program which controls the operations and management of resources of a computer system. ,
Control unit: The part of the central processor which directs the sequence of operations, interprets the coded instruction and sees the execution of program instructions.
Cost/benefit analysis : A procedure for evaluation and selection of hardware and/or software in which lists are made of all the costs and benefits of each proposed data processing system.
Counter: A device/register/ storage location for storing integers that are suitably incremented or decremented to represent the number of occurrences of an event.
CP/M (Control program/Microprocessor): A disk operating system.
CPU (Central Processing Unit): The control unit and the arithmetic logic unit of a computer system are jointly forms the CPU. All calculations and comparisons are done inside the CPU and the CPU is also responsible for activating and controlling the operations of the other units of a computer system..
CRT (Cathode Ray Tube): An electronic tube with a TV like screen upon which information may be displayed.
CSMA/CD (Carrier sense- multiple access/ collision detect): Here a transmitting node first tests the channel and if the channel is clear then transmits the desired message. If two stations transmit at the same time the collision is detected and retransmission is forced.
Cyber space : A synonym for the Internet. A term used by author Wilham Gibson for the shared imaginary reality of computer networks.
Cycle time: The time interval between the instant at which a read/write command is given to a memory and the instant when the next such instruction can be issued to the memory (also known as memory cycle time).
Cylinder : In a disk pack, a set of corresponding tracks in all the surfaces is called a cylinder. All tracks of a cylinder are accessible by a single movement of the access mechanism.

D
Daisy wheel printer: A letter-quality printer that uses a printing head with the appearance of daisy and/or a wheel. Each petal of the daisy wheel has a character pre embossed on it.
DASD : Acronym for Direct-Access Storage Device.
Data : A collection of facts in raw form that become information after proper processing.
Database : A collection of data files integrated- and organized into a single comprehensive file system which is arranged to minimize duplication of data and to provide convenient access to information within that system to satisfy a wide variety of user needs.
Data communications system : A system consisting of carriers and related devices used to transport data from one point to another.
Data dictionary : The document that contains clear definitions of the data that will be used in setting up data base management systems. .
Data element: A meaningful collection of related characters.
Data entry: The process of entering new data into computer memory typically from a keyboard.
Data file : A file consisting of data distinct from a program file of executable instructions.
Data Flow Chart: A flow chart showing the path of the data step by step in a problem solution or through a system.
Data processing: A series of operations that convert raw facts (data) into useful information
Data processing system: A system that accomplishes data processing. It includes the necessary resources, which are people, materials, facilities, and equipments..
Data processor : A digital device that processes data.
Data transfer rate : The speed at which data is transferred from the main memory to another medium on which data are recorded.
DBMS (Data Base Management system): The software, used for the management, maintenance and retrieval of the data stored in a data base.
Debugging: Process of finding/ correcting program errors (bugs).
Decision symbol: A diamond-shaped symbol used in flowcharts to indicate a choice or branch in the processing path.
Decision table : A table used for representing program logic. It displays the different conditions that could exist and the different actions that the computer should take as a result of these conditions.
Design phase : A phase in the life-cycle of a software system during which the detailed design of the system is carried out.
Desktop Publishing Packages : Software that combines text and graphics manipulating capabilities to allow users to format charts and pictures with text and headlines.
Desktop Publishing System : A system that combines a computer and suitable peripherals with software that can produce attractive page layouts complete with pictures and text printed in a variety of typefaces.
Development phase : A phase in the life-cycle of a software system during which a system is constructed to meet the requirements specified in the design phase.
Diagnostic routines : Programs used to print error messages by a computer to indicate system problems and improper program instructions.
Dictionary Disk : It contains the dictionary files, which are used for checking spelling.
Digital Computer : A computer that works with discrete quantities. It uses numbers to simulate real-time processes.
Digitizer: An input device used to convert graphic and pictorial data into binary, numeric inputs for a digital computer.
Direct access : A storage devices where the access time is effectively independent of the location of the data.
Directory access protocol (DAP): A protocol governing communication between a directory’s user agent and a directory’s system agent.
Disk : A flat, circular plate coated with a magnetic material on which data can be stored by magnetization of portions of the flat surface.
Disk operating system (DOS): An operating system which contains the disk-oriented commands and uses disk devices for permanent storage.
Disk pack : A removable direct-access storage medium containing multiple magnetic disks mounted vertically on a single- shaft.
Diskette : A low-cost, thin flexible magnetic disk storage device used on small computer systems..
Distributed data processing (DDP) : The decentralization of a computer system through the use of multiple computers interconnected by a communications network.. It facilitates data processing capabilities at the location of the end-user.
Document reader: An optical input device that is used to read documents printed in a special type font.
Documentation : It involves collecting, organizing, storing and otherwise maintaining a complete historical record of programs and other document used or prepared during the different phases of the system.
Downtime : The period during which a computer is malfunctioning or not operating correctly due to machine failures.
Drum printer: A line printer that uses a solid, rotating, cylindrical drum on which the characters to be printed are embossed.
Dumb terminal: A terminal that has no local processing capability.
Dump: A process whereby the contents of. all or a part of primary storage are copied onto some secondary storage device or displayed on a printer or screen.
Duplex : A data communication facility on which data can be transmitted in two directions.

E
EBCDIC (Extended Binary Coded Decimal Inter-change Code): An 8-bit coding system developed by IBM that is used to represent characters in many modem computers.
Edit: To modify format of the data.
Edit mode: A mode of operation in which a program accepts changes in the contents of a document.
Editor: Software used to interactively review and modify text materials and other program instructions.
EDP (Electronic Data Processing) ; A data processing through equipment that is predominantly electronic such as digital computer.
EDVAC (Electronic Discrete Variable Automatic Computer): An electronic computing device similar to the EN1 AC although faster, and having greater capability. It was built in 1952.
Electronic funds transfer (EFT): A cashless approach used to pay for goods and services. Electronic signals between computers are often used to adjust the accounts of the parties involved in a transaction.
Electronic Mail/Message System (EMMS): A system that can stare and deliver by electronic means, text and messages that would otherwise, be forwarded through the postal service or sent verbally over telephone lines.
Electronic mail : A general term to describe the transmission of messages by the use of computers and telecommunications facilities.
Electronic spreadsheet: An application package usually available with microcomputers that displays the equivalent of a work sheet made up of rows and columns. It is used for computation or display of information in a tabular form.
Electrostatic printer: A high-speed printer that uses charged pins to form character matrices on chemically treated paper.
Electro-thermal printer: A high-speed printer that uses heated elements to create characters as matrices of small dots on heat-sensitive paper.
Elementary data item: A data item which is not broken down into smaller units
Emulator: A program that permits one computer to execute the machine-language instructions of another computer of a different make.
End user: Any individual who uses the information generated by a computer based system.
ENIAC (Electronic Numerical Integrator and Calculator): The first all-electronic digital cumputerr developed by Mauchly and Eckert around 1946.
EPROM (Erasable Programmable Read Only Memory): A semiconductor memory which allows the eraser of the information stared in it so that new information can be stared in it.
Execution error: An error detected during the execution of a program.
Execution time: The total time required to execute a program on a particular system.
Executive routine: A master program in an operating system that controls the execution of other programs.
Extended ASCII : It provides added capability by allowing for 128 additional characters. The codes used in extended ASCII represents the additional values made possible bv using all 8 bits is a byte for coding (as opposed to the 7 bits used for the standard ASCII character set).

F
Facsimile (FAX): Transmission of images scanned at a transmitting point and duplicated at a receiving point.
FAQ (frequently asked question): A file containing frequently asked questions and their answers.. Many mailing lists and Usenet newsgroups maintain FAQ’s to so that participants will not have to spend lot of time answering the same set of questions.
Feasibility study: A study to determine whether the proposed solution is technically and economically feasible in all respect.
Fiber optic cable : A data transmission medium made of tiny threads of glass or plastic that can transmit huge amount of information at the speed of light.
Field: In a record a meaningful collection of one or more related characters treated as a unit.
File: A collection of related records.
File Management System (FMS): A software package that allows users to define data items, place these items into specified records, combine these records into designated files and then manipulate and retrieve stored data in various ways to achieve user’s goals. An FMS can typically access records from only one file at a time.
Flip-flop: A sequential electronic circuit which can be placed in one out of two stable states. Each state may be used to represent a binary digit.
File server architecture: A configuration of computers on a network similar to a client/server architecture except that the server is mostly a repository of a data on which it cannot itself perform queries or processing. When a client needs to make a query, the server sends all data that could possibly be relevant over the network, which is not efficient
FireWire: Like Access bus, it is a new high-speed desktop serial bus. Firmware: A sequence of instruction (software) that is substituted for hardware and stored in read-only memory (ROM).
First-in, first-out (FIFO): A technique for processing jobs on a first-come, first-served basis.
First generation computers : Computers built between 1949 and 1955 which used vacuum tubes and were programmed in assembly language. For examples are ENIAC. EDVAC, EDSAC.
Fixed-head magnetic disk: A magnetic disk system that eliminates the use of an access mechanism by distributing all the read/write heads over the disk surfaces.
Floating-point numbers: Signed numbers held in a fraction-exponent format.
Floppy disk: See diskette.
Flowchart: A pictorial representation that uses pre-defined symbols to describe either the logic of a computer program (program flowchart) or the data flow and processing steps of a system (system flowchart).
Flow-line: In a flowchart, flow lines with arrowheads indicate the flow of operation, i.e., the exact sequence in which the instructions are to be executed.
Footer: One or more identifying lines printed at the bottom of a page.
Foreground processing: Automatic execution of high-priority (foreground) computer programs that have been designed to pre-empt the use of computer resources. Contrast with background processing.
Format: The arrangement of input data/ stored data./ output information.
Formatting: For documents, the elements of style and presentation that are added through the use of margins, indents and different sizes and styles of type.
FORTRAN (FORmula TRANslation): A high-level mathematically oriented programming language used for scientific and engineering applications.
Fourth generation computers: Computers built between 1975 and till date. They use large scale integrated circuits, semiconductor memories and powerful high-level languages and operating systems.
Frame : The basic package of information on a network channel.
Frequency division multiplexing: A method used to concurrently transmit data between several transmitters and receivers over a single transmission medium.
Front-end processor : A CPU designed specifically to handle the communications processing task.. Its main purpose is to off-load communications processing task from the host computer so that the host computer can be dedicated for applications and data processing jobs.
Full adder: An adder which adds three binary digits and outputs a result bit and a carry bit.
Full duplex: A method of using a communication channel in which signals can be transmitted between a source and a destination in both directions simultaneously.
Function Key: A special key on a computer keyboard or a terminal device keyboard that is used to perform specific functions. These keys are programmable so that a software product can put the function keys to specific uses. Many keyboards have function keys labeled from F1 to F10.

G
Gateway: A device that is used to interface two otherwise incompatible network facilities.
Generator: A computer program that constructs other programs to perform a particular type of operations..
GIGO (Garbage in – garbage out): Pertains to the fact that most computer errors are not machine errors, they are data errors caused by incorrect input data. Thus incorrect input data results in inaccurate output.
Graphic display terminal: A visual display terminal which has screen to display a graph or drawing as well as alphanumeric information.

H
Hacker: A computer adept, some one who enjoys working with computers and testing the limits of systems. Also suggest someone who breaks into computer network and steals or vandalizes information. And on the Internet such malevolent hacker are called crackers)
Half adder: An adder which adds two binary digits and outputs a result bit and a carry bit (if any).
Handshake: A trade term that refers to what takes place when two computers or a computer and a terminal device are interconnected in such a way that they can exchange information.
Hard copy: Printed or filmed output from a computer device in human readable form.
Hardware: The physical components of a computer system such as electronic, magnetic and mechanical devices. Header: In word processing and printing one or more identifying lines printed at the top of a page.
Hierarchical network: A communications network in which computers or processors are connected in a tree-like structure.
Hierarchical structure: A tree-like structure used to represent files and records in a data base system.
High-level language: A programming language whose structure is application oriented and is independent of the structure of the computer.
Host computer: The main control computer in a network of distributed processors and terminals.
HTTP (Hyper text transport protocol): Internet protocol that defines how a Web server responds to requests for files made via anchors and URLs.
Hybrid computer : A combination of an analog and a digital computer. These computer systems utilize the measuring capability of an analog computer and the counting capability of a digital computer.

I
I/O (Input/Output): Pertaining to the techniques/ media/ devices used for man-machine interaction.
I/O bound jobs: Jobs that require more of Input/Output (I/O) operations as compared to computational operations. IDE (Intelligent Device Electronics): Any drive with integrated controller.
Indexed file: A file that includes an index directory to facilitate random access.
Indexed Sequential Access Method: A method whereby records are organized in a sequential order and can be referenced directly through an index) based on some or characteristic;
Indexing: It is an alphabetical listing of topics, words and phrases accompanied by the page numbers where each topic word or phrase can be found.
Information : The result of data processing which can be used to help a individuals to make decisions.
Ink jet printer: A printing device uses nozzles and sprays ink onto paper to form the appropriate characters. Input: The source data entered into a data processing system.
Input device: A device used to enter information into a computer or other data processing devices.
Instruction: A command or order given to a computer.
Integrated Software Package: A software product that combines several applications Intelligent terminal: A terminal having local processing capability.
Inter record gap (IRG): The separation or gap between records on a tape.
Interactive system: One that permits direct communication and dialog between system users and the operating program in the CPU.
Interface: Electronic circuit used to interconnect 1/O devices to a computer’s CPU or memory.
Internal storage : The addressable storage in a digital computer which is directly under the control of the CPU.
Internet Adapter (Telephonic IA) : A Unix program that enables a dial-up shell account to emulate a SLIP connections, allowing the user to run Internet software native to his or her desktop environment without the full costs/full functionality of real SLIP.
Internet work packet exchange (IPX): Novell’s NetWare network layer protocol that specifies addressing, routing and switching packets between a server and workstations and across interconnected LANs. Encapsulated IPX packets can be carried by Ethernet packets and token ring frames.
Interpreter: A language processor that translates a statement of a high-level language and immediately executes it before translating the next source language statement.
Inter process communication: The topology provided by an operating system to allow concurrent processes to communication with each other.
IOCS (Input/Output Control System): Set of routines for handling the many detailed aspects of input and output operations.
ISO protocol: A communication protocol to interconnect geographically dispersed heterogeneous computers. Item: A group of related characters treated as a unit.
Iteration: These are defined as repetitive execution of programming steps.

J
Job: A collection of specific tasks constituting a unit of work for a computer.
Jump: An instruction or signal which conditionally or unconditionally specific the location of the next instruction and directs the computer to that instruction. A jump is used to alter the normal sequence control of the computer.
Justify: To align lines of text evenly along both the left and right margins of a column or page.

K
Key-to-disk: A device used to enter data onto a disk device,
Key-to-tape: A device used to enter data onto a magnetic tape.
Key field: A unique field in a record used to distinguish one record from another.

L
Label: One or more characters used to identify a statement and instruction, or a data field in a computer program. Label record: A machine-readable record that is used to identify a data file. It is the first record of the file.
LAN (Local Area Network) : A digital communication system capable of interconnecting, a large number of computers, terminals and other peripheral devices within a limited geographical area.
Language processor : Software used to convert source program instructions to object or machine language instructions.
Laser printer: Printer that uses a combination of laser-beam and electro-photographic techniques to create printed outputs.
Library routine: A tested routine maintained in a library of programs. These programs can be called and used by other programs for a specific function.
LIFO (Last In/First Out): A queuing technique in which the next item retrieved from a queue is the one that was most recently placed in the queue.
Light pen: A pen shaped device that is used as an input device to computers by writing or sketching on the screen of a cathode ray tube.
Line printer: Printer that prints one line at a time.
Link: A communication path between two nodes or channel.
LISP (LIST Processing): A high-level programming language suitable for handling logical operations and non-numeric applications.
Logical error: An error that occurs when the actual logic of a program is different from the desired logic.
Logical operators: Symbols used to show a logical relationship between two data items.
Logical topology : The geometric arrangement of the nodes and links of a network as they function to support information transfer in the network.
Loop : A sequence of instructions that is executed repeatedly until a terminal condition occurs.
Low-Level languages: Programming languages that normally translate from one source instruction to one object instruction. These languages are machine dependent.

M
Machine language: A low-level language that is directly understandable by the computer system. Each model of a computer has a unique machine language.
Macro: A set of instructions that takes the form of one statement in an assembler language.
Macro flowchart: A flowchart that outlines the main segments of a program or that shows less detail.
Macro instruction : An instruction in a source language that is equivalent to a specified sequence of machine instructions.
Magnetic-ink character recognition (MICR): An input-device that can read cards and paper documents printed with a special magnetic ink.
Magnetic bubble memory: An electronic secondary storage device constituted of solid-state electronic chips and having no moving parts. It uses the properties of certain materials, under applied magnetic fields to represent binary 1 and 0.
Magnetic core: Tiny rings made of magnetic material that can be polarized to represent a binary 1 or 0. Magnetic disk: See disk.
Magnetic storage: Storage devices such as disks, drums, tapes, cores, etc. that utilize the magnetic properties of materials to store data.
Magnetic tape : A secondary storage device that uses a long plastic strip coated with a magnetic material as a recording medium.
Message handling service (MHS) : An E-mail protocol for storage, management and exchange, especially in corporate offices.
Mass storage: Referred to storage where large volumes of backup/ data is stored.
Master file: A file containing relatively permanent data. This file is often updated by records in a transaction file. Megabyte: bytes.
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Memory: A device / medium that accept data hold it and deliver it on demand.
Memory dump: A printout of the contents of memory.
Menu: A list of options from which a program user can select anyone in order to perform a desired action. Merging: Combining records from two or more ordered files into a single ordered file.
Message switching: A method whereby messages to be transmitted between computers are all sent to a central computer, which gathers them and routes them to the appropriate destination(s)..
Microcomputer: The smallest category of computer fabricated using a microprocessor and other integrated circuits. Microprocessor: A LSI chip which contains the entire CPU of computer except main memory.
Micro program: Firmware programs residing in read-only memory (ROM) which aid the control unit in directing the operations of a computer system.
Microsecond: One-millionth of a second.
Millisecond: One-thousandth of a second.
Minicomputer : A relatively fast but small and inexpensive computer with somewhat limited input/output capabilities.
Mnemonic: Any kind of mental trick one use to help him remember.
Modem (Modulator-demodulator): Devices used to convert digital signals (to be communicated over an analog channel such as telephone line) to Sine waves at the sending end and back to digital signals at the receiving end.
Modular approach : Dividing a project into segments and smaller units in order to simplify the analysis, design and programming effort.
Modulation : The technique by which a digital signal is converted to its analog form for transmission over an analog facility.
Monitor routine: See executive routine.
Mulultiplexing : The method of dividing a physical channel into many logical channels so that a number of independent signals may be simultaneously transmitted on it.
Multiprocessing: A term used to describe interconnected computer configurations or computers with two or more independent CPUs that have the ability tq simultaneously execute several programs.
Multiprocessor: A computer system consisting of more than one CPU under a common control.
Multiprogramming: The inter-leaved execution of two or more different and independent programs by the same computer.
Multi-threading : It is a facility available in an operating system that allows multiple functions from the same application package.

N
Narrowband channel : Communication channels that handle low volumes of data. They are used mainly for telegraph lines and low speed terminals.
Network : An inter-connection of computer systems and/or peripheral devices with carriers and data communications devices for the purpose of exchanging data and information.
Network adaptor card : A card used in IBM compatible computers to permit their user on a particular type of network.
Network topology: The structure of interconnecting of nodes of a computer network.
Nibble: 4 bits, half a byte.
Node : An end point ,of a branch in a network or a common junction of two or more network branches.
Non-document file: Pure ASCII files that can be listed for any word processing software.
Non impact printer: A printer that prints without banging a ribbon onto paper i.e., thermal, ink jet, laser printers.
Non volatile storage: A storage medium that retains its contents even in the absence of power.

O
Object language : The output of a translation process opposite to source language.
Objectpriented: A computer program and its data are modeled as a group of autonomous objects that respond to messages sent by one to another. The internal structure and processes of each object are in principle invisible to other objects.
Object program: A fully compiled or assembled program that, is ready to be loaded in the computer. The results from the translation of a source program by a language processor.
Octal number system: A number system with a base of 8. The octal digits range from 0 to 7.
Off-line: A device or system not directly connected to the CPU.
On-line: A device or system directly connected to the CPU.
Operand : The part of a machine level instruction which tells the central processor the location of the data to be manipulated.
Operating system: An integrated set of programs used to manage various resources and overall operations of a computer system.
Operation code (op code): The part of a machine level instruction which tells CPU what has to be done. Operation phase : The life-cycle phase during which the system constructed in the development phase is used. Optical bar-code reader: An input device that can interpret combinations of marks (bars) that represent data.
Optical Character Reader (OCR): An Input device which can read characters directly from all ordinary piece of paper by using a scanning mechanism. These characters are written in special type fonts.
Optical Mark Reader (OMR): An input device that can interpret pencil marks on paper media.
Output: The finished result of processing by a system.
Output unit: The unit of a computer system that supplies information and results after processing to the outside world.
Over lapped Processing: An approach that permits the computer to work on several programs instead of one.

P
Packet Switching: A method of communication between computers in a network in which blocks of messages to be transmitted are formed into packets and placed on the channel. Each packet contains source and destination addresses, synchronizing, error correction and control bits. The packets are routed using the source and destination addresses.
Page break: The point at which the flow of text in a document moves to the top of a new page.
Page reader: A high-capacity optical input device that is able to scan and interpret an entire page that is typed in a special font.
Paging: A technique to implement virtual memory. Here memory is divided into units of fixed size memory.
Paper tape punch : An output device that converts data from a binary format in the main storage to coded hole- patterns, punched into paper tape.
Parallel adder: An adder where all the bits of the two operands are added simultaneously.
Parallel operation: A system changeover method whereby data is processed by both the old and the new system until the performance of the new system is verified satisfactorily.
Parity bit: An extra bit added to a string of bits that enables the computer to detect internal errors in the transmission of binary data.
Pascal: A high-level programming language named after Blaise Pascal that facilitates structured programming techniques.
Password: A code by which a user gains access to a computer system, used for security purposes.
Peer-to-peer: A description of communications between two equal devices.
Pixel: A picture element. It is used to represent one point in a raster scan display device.
PL/I (Programming Language One): A high level programming language designed for handling both scientific and business applications.
Plotter: An output device that converts computer output into a graphic hardcopy form.
Point-of-sale (POS): A device able of immediately updating records at a central CPU and sales transaction receipt.
Peripherals devices: Since the input and the output devices are on the periphery (edge) of the main processing unit therefore they are referred as peripheral devices.
Personal computer (PC): A small and inexpensive computer (usually a microcomputer) used by individuals for personal applications.
PERT (Program Evaluation and Review Technique) : A technique used to facilitate the implementation of a computer system.
Phase modulation: A form of modulation in which two binary values of digital data are represented by the shift in phase of the carrier signal.
Phased replacement: A system changeover method in which the complete changeover to the new system takes place incrementally over a period of time.
Physical topology: The geometric arrangement of the links and nodes of a network as they physically appear to an observer.
Pico second: One trillionth of a second.
Pointer: A data item in one record that contains the location address of another logically related record.
Point-to-point protocol (PPP): A TCP /IP protocol similar to SLIP for transnlilting IP data grams over serial lines such as phone lines. With PPP, PC users can connect to the Internet and still function in their native environment.
Portability: An ability of a program to run on different types of machines with minimum modification.
Post office protocol: A protocol that specifies how a personal computer can connect to a mail server on the Internet and download E-mail.
Primary memory: A section of the CPU that holds program instructions, input data, intermediate results and the output information produced during processing. Also known as primary storage, internal storage and main memory.
Printer: An output device used to produce hard copy of computer output that is readable by human beings.
Problem-oriented languages : High-level programming languages designed for the convenient expression of a given class of problems.
Procedure-oriented languages : High-level programming languages designed for the convenient expression of procedures used in the solution of a wide class of problems.
Processing: Performing arithmetic operations / logically manipulating to input data in order to convert them into a desired output.
Processing symbol: Rectangular figures used in flowcharts to indicate a processing operation.
Processor: A unit of a computer system that interprets instructions and executes them.
Program: A set of sequenced instructions used to direct and control the operations of the computer In order to solve a problem or to perform a particular
Program counter (PC): A register in CPU which is used to store the address of the next instruction to be executed.
Program library: A collection of complete programs, subroutines, and program modules that have already been developed, tested and documented to be used by programming projects.
Programmer: One who designs, writes, tests and maintenance computer programs.
Programming Language: A language used to express algorithm in computer understandable form.
PROM (Programming Read-Only Memory): Similar to read only memory with the exception that these chips can be reprogrammed by using special external equipments.
Prompt: One or more symbols used by the computer to indicate it is ready for data input from a user.
Pseudo code: A program analysis tool that is used for planning program logic. It is an imitation of actual computer instructions written in ordinary natural language such as English.

Q
Queue: An alternate pipe form of operating system, which handles data in the form of messages rather than bytes.
Query • A statement that extracts information from the database. Most often selecting the information based on a predicate.

R
Radix: Same as base.
Random access memory (RAM): A storage device in which the time to retrieve stored Information is independent of the address where it is stored.
Re-director: A part of the network software that translates a virtual resource request from the user to real resource on a server.
Real-time systems : Pertains to on-line computer processing systems which receive and process data quickly enough to produce output to control direct or affect the outcome of an on going activity or process.
Record: A collection of related items of data treated as a unit.
Record length: A measure of the size of a record.
Register: See local storage.
Relational Data Base Management Package: Software that manages data in more than one file at a time and these files are treated as tables with rows and columns rather than as lists of records.
Resident Program: A program that remains in the memory whiles other programs are executing.
Response time: The total time elapsed between submission of command and data to a computer and getting the result of computation.
Ring network : A computer network in which there is no host computer for controlling other computers and in which all stations are equal.
Robot: An automatic machine that performs routine human tasks.
ROM (Read Only Memory): Special memory chips containing instructions which can be read only, therefore preventing accidental destruction of the instructions. ROM is used to store firmware.
Rotational delay: In a disk storage the time taken for a record contained on one of the sectors to rotate under the read /write head.
Routine: See program.
Routing : The process of choosing the best path throughout the LAN.
Run time: The time required to complete a single, continuous execution of a object program.
Run-time error: See execution error

S
Scrolling: The use of program-specified keys to quickly move through a word processing document or spreadsheet to locate the desired material.
Search and Replace: Here the user can specify two strings of characters- one string for the program to find and replace with the second string. Second generation computers: Computers built during the period 1955-64 which used transistors in CPU, magnetic core main memories and high-level languages like FORTRAN and COBOL for programming.
Secondary storage: See auxiliary storage.
Seek time: In a disk system time required for a read/write head to move to the track where the record to be read or written is stored.
Segmentation: A method of providing virtual memory.
Semiconductor storage: A storage device whose elements are formed as solid-state electronic components on an integrated circuit chip.
Sequential processing : A technique in which a number of similar items or transactions to be processed are grouped together and processed in a designated sequence.
Serial access: A storage device or medium where the access time is dependent upon the location of the data. Serial adder: An adder in which the bits of the operands are added one after another.
Serial line Internet protocol (SLIPS): A TCP /IP protocol for transmitting IP datagram over serial lines such as phone lines. With SLIP personal computer users can connect to the Internet and still function
Server: A system that shares resources with one or more work stations on a network.
Simple mail transfer protocol (SMTP): The TCP /IP protocol that specifies how computers exchange electronic mail. It works with post office protocol and is one of the reasons that Internet E-mail functions well.
Simplex: Transmission of data in one direction.
Simple network management protocol (SNMP): A TCP /IP protocol that specifies how nodes are managed on a network using agents to monitor network traffic and maintain a management information base.
Simulation: To represent and analyze properties or behavior of a physical or hypothetical system by the behavior of a system model.
SNOBOL : An acronym for string oriented symbolic language. A high-level language designed to manipulate strings of characters and used for nonnumeric applications.
Soft copy: Computer output which is displayed on the screen of a terminal without a permanent copy.
Software: The set of computer programs, procedures, and associated documentation related to the effective operation of a computer system.
Solid state: Electronics components whose operation depends on the control of electric or magnetic phenomena in solids such as transistors and diodes.
Sort: The process of arranging data into a desired sequence.
Source document: A document on which data that are to be recorded in machine-readable code originates.
Source program/Code: A program written in a symbolic or high-level source language such as assembly language.
Special character: A graphic character that is neither a letter, a digit, nor a space character i.e., @,$,* etc.
Speech recognition: The ability to input data directly into a computer system by speaking to it.
Speech synthesis: Computer output in the form of spoken word..
Spelling Checker: Software that checks every word in a document against an electronic dictionary of correctly spelled words.
Spooling : A technique that has been successfully used on a number of computer systems to reduce the speed mismatch between slow speed I/O devices and fast CPU.
Stack: A memory in which the information stored last is on top and is retrieved first..
Star network : A network having a central host computer system that is attached to local computers through multiple communication lines. The local computers are not linked directly to each other and can communicate only via the host computer.
Statement: In programming, an expression or generalized instruction in a source language.
Storage: See memory.
Store and forward method: A method of message transmission in a computer network in which messages are sent to a central computer which receives, stores and forwards them to the specified destinations.
Structure Chart: A pictorial representation of the design of a system. It shows step by step path of data through the system.
Structured design: A system design approach in which a difficult problem is broken into smaller problems that are small enough to manage but independent enough to solve separately.
Structured programming: An organized approach to programming involving the use of three basic control structures – sequence, branch and loop and the use of top-down concepts to decompose main functions into lower-level components for modular coding purposes.
Study phase: A system life-cycle phase during which a problem is identified, alternative solutions are studied and the most feasible solution is selected.
Subroutine : A standardized program written in such a way that it can be used as a part of another program whenever necessary. A subroutine is normally invoked through other programs by the GALL statements.
Subsystem: A system that is a part of a larger system..
Supercomputer: Computer systems characterized by their very large size and very high processing speeds. Used for complex scientific applications.
Swapping: Storing programs on disk and then transferring these programs into main storage as and when they are needed. The technique is used to process large programs or several programs with limited memory.
Symbolic code: Computer instructions written with the use of English words and mathematical symbols instead of binary machine code. Symbolic code is also called source code or source program.
Syntax: The set of rules of a programming language that define the pattern or structure of the word order and punctuation of an instruction.
Syntax errors: Errors in computer programs that typically involve incorrect punctuation, incorrect word sequence, undefined terms or misuse of terms. These errors are automatically detected and pointed out by language processors.
System: A group of integrated parts (people, methods, machines, and materials) that have the common purpose of achieving some objective(s).
System analysis: A detailed step-by-step investigation of related procedures to see what must be done and the best way of doing it.
System analyst: The individual responsible for planning a computer data processing system, utilizing tools like flowcharts, decision tables, program design language etc. These plans are then passed to the computer programmer.
System Commands: Commands used to communicate with the operating system of the computer.
System flowchart: A flowchart that uses predefined symbols to describe data flow in a system.
Systems programmer: A person who prepares system programs that are a part of the operating system designee to simplify the use of the computer.
Systems software: A set of one or more programs designed to control the operation of a computer system. They are general programs written to assist humans in the. use of computer system and for making the operation of the computer system more effective and efficient.

T
Tape density: The amount of data that can be placed over a given length of tape, bytes or characters per inch.
TCP/IP: A protocol stack, designed to connect different network on which the Internet is based. The suite includes protocols for remote login, file transfer (FTP), E-mail (SMTP) and so on. TCP /IP can work with any hardware or operating system.
Tele-conferencing: A system in which persons sitting at CRT screens see and talk to each other via a computer- communications network.
Telecommunications : Transmission of data between computer system located at distances through telephone facilities.
Teleprinter terminal: A terminal that has a keyboard and a printing device.
Teletypewriter: An inexpensive input and output device that uses paper tape and is often used as a component of a small computer system.
Template: A plastic or metal guide used to trace flowcharting symbols.
Terminal: An input/output device which allows a user to communicate directly with a computer system.
Terminal symbol: A symbol used in flowcharts to indicate the beginning (START), ending (STOP) and pauses (HALT) in the program logic flow. •
Terminator: A device that attaches to both ends of an electrical bus and prevents reflection of echoes of signals that reach the end of the bus. It also makes sure that the impedance is correct.
Testing: The process ot making sure that the program performs the intended task.
Thermal printer: A printing device that utilizes paper that is sensitive to heat.
Third generation computer: Computers built between 1964 and 1975 that used integrated circuits in CPU, high speed magnetic core main memories, powerful high level languages and saw the advent of time sharing operating system.
Throughput: The total amount of useful processing carried out by a computer system within a given time period. It is a. measure of the efficiency of a computer system.
Time sharing: Refers to the allocation of computer resources in a time- dependent fashion to several programs simultaneously. It enables a large number of users to simultaneously use a computer for processing their jobs which may be of different nature.
Token-ring: A network system that uses a ring logical topology and a token channel access method.
Token: A channel access control method in which a token is passed between the nodes on the network: any station with the node at any particular time can then use the network channel..
Top-down approach: A disciplined approach to system design or program design in which top-level functions are decomposed into a hierarchy of understandable lower-level modules for better management and easy handling.
Transistor: A controlled electronic switch fabricated using a semiconductor. Used in the design of various electronic equipments.
Transponder: A device mounted on a communication satellite which receives, amplifies and retransmits signals’ from earth stations.
Turnaround time: The elapsed time between the submission of a job to a computer system and getting its output.
Turnkey systems: Special purpose systems in which a single vendor supplies not only the machine itself, but also all of the needed software.

U
Unbundled: A term which means that the application software is priced separately from the computer hardware.
Unconditional transfer: A program instruction that causes the program control to flow out of normal sequence unconditionally.
UNIVAC (Universal Automatic Computer): The first commercially available computer.
Universal Product Code (UPC): A universal or standardized optical bar code which normally appears on retail packages and which is read by a laser beam scanner.
UNIX: A popular operating system for 16-bit mini and micro computers.
Updating: The process of keeping master files accurate and up-to-date by processing them with the latest transactions contained in the transaction file.
User: Any individual who uses computer for different uses.
Utilities: Programs to perform some frequently required processes in the operation of a Computer system.

V
Validation: The process of making sure that the forms and documents from a particular transaction are correct.
Variable name: In a program the name assigned do a data field assume any of a given set of values.

Video Display Unit (VDU): An I/O device that consists of a television-like screen for displaying outputs and a keyboard for entering inputs.
Videotex System: A general term used to describe personal computing/communications networks that permit interaction between people and stored data bases.
Virtual memory : The technique of using disk space to make programs believe that the system contains more random access memory (RAM) than is actually available. This can be implemented by using pure segmentation, pure paging or a combination of both.
Virtual resource: A resource (printer directory etc.) that is used as if it was on a local workstation, but is actually located on a network server.
Virtual storage: The capability to use on-line secondary storage devices and specialized software to divide programs into smaller segments for transmission to and from internal storage in order to significantly increase the effective size of the available internal storage.
Virtual system: An extension of virtual storage concept. Here users can share all of the computer resources as if each user had his own computer.
VLSI (Very Large Scale Integration): An electronic circuit with about 10.000 transistors fabricated in a single silicon chip.
Voice recognition unit: An Input device used with voice recognition systems that converts spoken words into binary data suitable for input to the system.
Voice response unit: An output device that uses words or messages recorded on a magnetic medium to produce audio response.
Voice-band Data: A communications system that handles moderate volumes of data typically from 300 to 9600 bauds.
Volatile storage : A storage medium that loses its contents in the event of power failure.

W
Web (World Wide Web): An interlinked collection of hypertext documents (Web pages) residing on Web servers and other documents, menus and database available via URLs. Web documents are marked for formatting and linking with HTML, and Web servers use HTIP to deliver Web pages.
Wide Area Network (WAN): A digital communication system which interconnects different sites., computer installations and user terminals, and may also enable LANs to communicate with each other. This type of network may be developed to operate nationwide or worldwide and the transmission medium used, are normally public systems such as telephone lines, microwave and satellite links.
Winchester disk: Medium-sized. Non-interchangeable metal disks permanently housed in sealed contamination- free containers. Read /write heads are built-in with the disk. These disks are used with small, mini and personal computers.
Windows XP/ ME/2000/98/95 : Operating system by Microsoft
Word: A group of bits or characters considered as an entity and capable of being stored in one storage location..
Word length: A measure of the size of a word usually specified in units such as characters or bits. Each location of a computer system can store a fixed number of characters or bits called its word length.
Word processing: The use of computers to create, view, edit, format, store, retrieve and print text materials for human communication.
Workstation: An access point in a local area network for services provided by the network.