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Technology Terminologies (A to Z)

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Unwanted or meaningless information in memory, on disk or on a tape.


An electronic door between one computer network and another. A device or set of devices that connects two or more networks, enabling data transfer between them. When the networks are similar, a gateway routes packets or messages. When the networks differ, a gateway also performs extensive protocol conversion.


Graphic Interchange Format. Compuserves non-platform specific format for low-resolution, compressed graphics interchange.


A client program available via the Internet that allows users to review and retrieve information on other host systems via easy-to-use menus.


A computer-generated picture produced on a computer screen or paper, ranging from simple line or bar graphs to colorful and detailed images.


Software that serves the group and makes the group as a whole more productive and efficient in group tasks. Example: Group Scheduling.


Graphical User Interface. Defines a format for scroll bars, buttons, menus, etc., and how they respond to the user.


A procedure performed by modems, terminals, and computers to verify that communication has been correctly established.


When a computer freezes, so that it does not respond to keyboard commands, it is said to "hang" or to have "hung."

hard copy

A printed copy of machine output in a visually readable form.

hard disk

A data-recording system using solid disks of magnetic material turning at high speeds.


Physical computer equipment such as electrical, electronic, magnetic and mechanical devices.


Circuits that are permanently interconnected to perform a specific function, as distinct from circuits addressed by software in a program and, therefore, capable of performing a variety of functions, albeit more slowly. Also used to describe a non-switched connection between devices.


The portion of a message, preceding the actual data, containing source and destination address and error-checking fields.


Users in need of help can often issue a command such as "?" to access on-line help and tutorial systems.


A computer that is made available for use by multiple people simultaneously.

host computer

In the context of networks, a computer that directly provides service to a user. In contrast to a network server, which provides services to a user through an intermediary host computer.


Hypertext Markup Language. A convention of codes used to access documents over the World-Wide Web. Without HTML codes, a document would be unreadable by a Web browser.


HyperText Transfer Protocol. Extremely fast protocol used for network file transfers in the WWW environment.


A device that is a center of network activity because it connects multiple networks together.


A pointer that when chosen displays the item to which it points. It typically takes the form of a button or highlighted text that points to related text, picture, video, or audio. Hyperlinks allow non-linear exploration of media that contain them.


Media (such as text, graphics, video, audio) that contains hyperlinks.


A document which has been marked up to allow a user to select words or pictures within the document, click on them, and connect to further information. The basis of the World-Wide Web.

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