Glossary of Computer and Internet Terms

Computer Terms

Active matrix LCD panel High-resolution color display for laptop computers.

Application software Computer programs designed to directly deal with solving the user’s problems. Examples would include programs for accounting, word processing, financial analysis, computer games, etc.

Backup The act of making a second (backup) copy of the data stored on a disk or other storage device, to safeguard against loss of data if there is damage to the primary copy.

BASIC Acronym for Beginner’s All-purpose Symbolic Instruction Code. A general-purpose programming language, often used in computers.

Baud rate A measurement of the speed at which data are transmitted between two computers, the number of signal per second being transmitted.

Bit Abbreviation for “binary digit,” the most common unit computers use for representing data internally.

Byte A group of eight bits, the most common unit computers use for internally representing individual characters, digits, or other data.

Cathode ray tube (CRT) Another term for display screen.

CD-ROM Abbreviation for Compact Disk-Read Only Memory. A small disk device capable of storing extremely large amounts of data, but which cannot be erased and reused for storing other data (the reason it is referred to as “read only”).

Central processing unit (CPU) The part of a computer that controls the entire system and does mathematical processing of data.

Character A single digit, letter of the alphabet, or other symbol. Usually represented inside a computer by one byte.

Chip Common term for very small silicon wafers upon which electronic circuits have been created for use in computers. Used for microprocessors, electronic memory, and other internal computer electronic components.

Communications program Computer program containing the instructions that allow a computer to send data to and receive data from another computer.

CPU Central Processing Unit.

Cursor A block, underline character, arrow, or other symbol used on a display screen to indicate a particular location on the screen.

Data The symbols, writing, words, or other items used to represent facts, objects, events, or ideas. Accounting records and yield measurements are two examples of data.

Data base management system (DBMS) General-purpose computer program that allows data to be stored, manipulated, organized, and retrieved in some logical manner. Sometimes referred to as an “electronic filing program.”

Demonstration program Limited, incomplete version of a program offered for sale by a software company, used for demonstrating the complete program’s features and capabilities. Often given free to potential buyers of the complete program, or sold at low cost.

Disk drive Device for recording onto and reading from one type of computer storage disk—either a diskette, or hard disk. Varying sizes and types of disks are not interchangeable among disk drives.

Diskette A 3 1/2-inch or 5 1/4-inch floppy disk.

Display screen Usually a television-like screen used for displaying computer output, however, may also be an LCD or other device.

Documentation The printed operating instructions that accompany a computer or software.

Dot matrix printer Printer that forms characters by selectively coloring or inking dots in a grid or matrix of dots. Characters thus printed often appear to consist of rows of dots.

Electronic worksheet or spreadsheet A general purpose computer program that operates like a large columnar pad of paper in the computer’s memory, which can do calculations on data typed onto the sheet. Allows data and formulas to be typed in, edited, calculated, and printed out. Often used for budgeting and forecasting, as a “what if” planning tool.

Entry The act or result of putting data into a computer.

Ethernet A type of network interface card that connects an individual computer to a network. Computers on the Internet that use the TCP/IP protocols are frequently connected to the Internet over an Ethernet link.

Expert system A computer program for making a recommendation, which tailors its recommendation to the user’s situation by following a variable path of reasoning dependent upon data given it by the user. One example would be a program to recommend grain marketing strategies based on the user’s risk and profit goals, availability of storage, proximity to markets, etc.

FAX modem A device to connect computer to telephone line to send data FAX messages.

File A collection of related data existing upon a computer storage device.

Floppy disk Flexible plastic disk coated with a magnetic material, upon which computer programs and data may be stored. Usually from 3 to 8 inches in diameter.

Hard disk A type of computer storage disk, usually consisting of a metal platter coated with a magnetic material. Capable of storing larger amounts of data than floppy disks.

Hardware The physical parts of a computer.

Information The result of processing, manipulating, and organizing data in a way that adds to the knowledge of the person receiving it.

Ink-jet printer A low-cost, near laser quality printer that uses liquid ink.

Input The data put into a computer.

Keyboard Typewriter-like computer input device.

Kilobyte (K) A unit for measuring computer memory and storage capacity, roughly equal to 1,000 characters or bytes of data. Technically, one K is 1,024 bytes.

Laser printer A fast, high-quality printer.

LCD Liquid Crystal Display. A technology popular in watches and calculators for displaying information, which also may be used for computer display screens—especially in portable computers.

LAN Local area network

Megabyte One million bytes, or 1,000 kilobytes.

Memory Term usually referring to the electronic memory circuits of a computer; however, sometimes also extended to imply all memory and storage devices used by a computer.

Menu A list of choices displayed on a computer display screen, from which the user may choose a program action.

Microcomputer Any computer using a microprocessor as its central processing unit.

Minicomputer Term for computers intermediate in processing power between microcomputers and mainframe computers.

Modem A device that allows a PC to communicate and exchange information with other modem-equipped computers via telephone lines. The current standard for modems is 56k, which allows you to transfer data at up to 56,000 bits per second.

Monitor A display screen.

Mouse Computer input device consisting of a small box having one or more buttons on top, for giving instructions to a computer.

MSDOS Operating system program popular among users of the IBM-PC and compatible computers.

Operating system A program or collection of programs that coordinates and controls the various devices making up a computer system.

Output The act or result of printing or displaying information generated by a computer.

PCMCIA An international association that defines specifications for devices.

Peripherals The add-on hardware devices used in conjunction with a computer, printer, display screen, disk drives, etc.

Printer Device that transfers computer output onto paper.

Program A set of pre-defined commands or instructions that tells a computer how to go about solving a problem or doing some job.

Random-access memory (RAM) Electronic memory circuits in a computer that may be both read from and written to, and which lose the data they contain whenever electricity is turned off to the computer. Sometimes referred to as volatile memory.

Read-only memory (ROM) A memory device (usually electronic memory circuits) that may only be read by a computer. The data stored in ROM memory is permanent (non-volatile) and is not lost when electricity is turned off to the computer.

Small computer systems interface (SCSI) Used to connect hard drives and tape drives to computer.

Storage device Any device upon which a computer may store data in permanent form. Data is not lost from a storage device when the electricity to a computer is turned off, as is the case with electronic memory. Sometimes called non-volatile memory.

Surge protector Electronic device for protecting a computer or other electronic device from the harmful effects of sharp surges of voltage in electric power lines.

Template A pre-programmed set of instructions that may be used with an electronic worksheet or spreadsheet program for doing a particular job. Akin to a computer program.

Utility software Computer programs for handling the organizational and “housekeeping” chores in running a computer, such as deleting files of old data, copying disks, printing a directory of the information stored on a disk, etc.

WAN Wide area network

Word processing Using a computer to accept, edit, organize, and print out text.


Internet Terms

Address An individualized name (or number) identifying a computer user or computer. Used in network communications for the transmission of
messages for a particular person or machine.

Bookmark Most Web browsers give you an option of adding a URL to a list. By doing this, you can store the linking information (the URL) to any Web pages you plan to revisit.

Browser (Web browser) A software application (either text-based or graphical) that lets you browse (surf) the World Wide Web.

Cache (Pronounced “cash”) A region on the computer memory where frequently accessed data can be stored for fast access.

Chat room (or chatline) A location on an online service that allows users to communicate with each other about an agreed-upon topic in “real time” (or
“live”) as opposed to delayed time with e-mail.

Cookie Small bits of data that a Web page asks a browser to store on a user’s computer, either in RAM or on the hard drive.

Dial-up As opposed to a dedicated or leased line; a type of computer linkage using regular telephone lines, generally referring to the kind of connection one makes when using a terminal emulator and a regular modem.

Domain Name System (DNS) The unique name of a collection of computers connected to networks such as the Internet.

Download To receive a file sent from another computer via modem.

DSL (Digital Subscriber Line) A DSL circuit is much faster than a regular phone line. Currently DSL is not available in all cities or parts of cities.

E-mail (electronic mail) Online communications between computer users.

Encryption The process of scrambling a message so that a key, held only by authorized recipients, is needed to unscramble and read the message.

FAQ Frequently Asked Questions.

File compression This process stores computer data more efficiently so the information takes up less disk or file space and may be transmitted in less

Finger A program used to find out whether someone is online. It may also reveal his or her full name and project files.

Firewalls Special computers that are set up on a network to prevent intruders from stealing or destroying confidential files.

Flame To heap written abuse on other computer users or to excessively criticize them for their ideas, spelling, grammar, etc. Flaming is considered
impolite, juvenile behavior, but it is not uncommon in some newsgroups.

Freeware Noncopyrighted software made available free for public use by the author.

FTP (File Transfer Protocol) The process of transferring files or pro-grams from one computer to another. An FTP site is a computer on the Internet that stores files and provides access to them.

GIF Graphic Interchange Format, the most common format used for graphics on the Internet.

Helper applications Additional software occasionally needed to help a Web browser program deal with a specialized file on the Internet.

Home page An introductory WWW page or Web server at a Web site that provides hyperlinks to other Web pages.

HTML (HyperText Markup Language) The computer language used to create hypertext documents. A system of marking up, or tagging, a document so it can be published on the World Wide Web.

HTTP (HyperText Transfer Protocol) The client-server protocol upon which the World Wide Web is based.

Hyperlink, hypertext A link within one document connected to other documents, other places within the same document, pictures, or HTML pages. Think of a hyperlink as an invitation to visit another place. A simple click on the link will take you there.

Internet The worldwide network of networks based on the TCP/IP protocol. A noncommercial, self-governing network devoted mostly to communication and research with roughly 66 million users worldwide.

Internet Service Providers (ISP) An organization that lets users dial into its computers to connect to its Internet link for a fee. ISPs generally provide an Internet connection and an electronic mail address. Some providers also include World Wide Web browsing software.

Intranet Internal networks, based on Internet technology, designed to connect the members of a specific group or single company (a closed-user group).

IP (Internet Protocol) Main protocol upon which the Internet is based.

ISDN (Integrated Services Digital Network) Telecommunications network that allows for digital voice, video, and data transmissions.

JPEG (Joint Photographic Experts Group) A format that is used to display graphics on Web pages.

Listserv A program that allows users to mass-distribute messages that form conferences, as well as archiving files and messages that can be searched for and retrieved.

Login, logon The process of identifying yourself to your computer or an online service. The initial identification procedure to gain access to a system as a legitimate user. The usual requirements are a valid user name (or user ID) and password.

Logout, logoff The concluding steps for formally ending a session with a system. Physically disconnecting or powering down a terminal does not necessarily result in a logout.

Mailing list Electronic discussion groups that link a relatively small group of people together by common interests and that are distributed throughout the Internet via its global e-mail system.

Multimedia Documents or platforms that combine different kinds of data (text, video, graphics, audio).

Netiquette Guidelines to good manners on the Internet; for example, don’t flame other users, don’t leave your caps lock key on (that’s like yelling), etc.

Newsgroup Collection of information and users who get together to communicate about one particular subject.

Online Refers to the successful connection with another computer via telephone lines or through a network.

Online service A dial-up service that provides news, information, and discussion forums for users with modem-equipped PCs and the access software provided by the service.

PDF (Portable Document Format) A PDF file preserves the look of a document. It is commonly used to make available publications on the Web. A free Acrobat Reader is needed on a computer before PDF files are readable. The Reader can be downloaded from the Adobe Corporation web site at

Privacy Policy Web sites should have a statement that describes what information about you is collected by the Web site and how it is used. A good policy statement should have an opt-in or opt-out option. An opt-in option means that the Web site will not use your information unless you tell them
they can. An opt-out option means that the Web site can use your information.

Protocol The “must follow” regulations that govern the transmission and receipt of information across a data communications link.

Script Also known as calling script. A record of keystrokes and commands that can be played back in order to automate routine tasks, such as logging on to an online service.

Search engine A WWW site that serves as an index to other sites on the Web.

Server A computer (or service) that provides information or a service to other computers on a network.

Shareware Software that is sold by individuals or companies for a nominal fee. Typically the software is downloaded and tried out before buying and
registering it.

Signature A three- or four-line message, used to identify the sender of an e-mail message or Usenet article.

Spam Generally referred to as the Internet equivalent of junk mail, spam ranges from annoyances like mass e-mailings and advertisements, junk mail,
and chain letters, to fraudulent product or service promotions, and harassing or threatening e-mails.

T-1, T-3 line High-speed digital lines that provide data communication speeds of 1.544 megabits (T-1) and 45 megabits (T-3) per second.

TCP/IP (Transmission Control Protocol/Internet Protocol) A set of instructions that dictates how packets of information are sent across multiple
networks. This includes SLIP and PPP. Also included is a built-in error-checking capability.

Telnet A program that lets the user log onto a remote computer. Also, the name of the program implementing the protocol.

Upload To send or transmit a file from one computer to another via modem.

URL (Universal Resource Locator) A Web site’s address. An example is: (ISU Extension’s home page).

Usenet Refers mostly to the newsgroups, but also to e-mail. Usenet travels on the Internet, but also over modems and satellites.

Username, user-id An address that designates a personal account on a large computer. For example, in, “jsmith” is the user-id.

Virus A piece of programming code inserted into other programming to cause some unexpected and usually undesirable event, such as deleting or damaging files.

Web server A computer that is connected to the Internet that stores and manages Web documents. A Web server handles requests from other computers and delivers requested Web documents.

Web site A group of related pages, images, and files on a Web server.

WWW (World Wide Web) One of several features of the Internet. It contains graphics, video, audio, text, and much, much more.


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