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Technology Terminologies

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machine language

A programming language or instruction code that is immediately interpretable by the hardware of the machine concerned.


A single computer instruction that stands for a given sequence of instructions.

magnetic disk

A flat circular plate with a magnetizable surface layer used for storage of data.

magnetic tape

A tape with a magnetizable surface layer on which data can be stored by magnetic recording.


A file of e-mail messages on which a UA can operate as if they were incoming messages (read, reply, forward, delete, etc). Compare with inbox.

main memory

Usually the fastest storage device of a computer and the one from which instructions are executed.


The cabinet that houses the central processing unit and main memory of a computer system, separate from peripheral devices such as card readers, printers, disk drives, etc. and device controllers. The term has come to be applied to the computer itself in the case of large systems. A large computer system; the IBM ES9000.

mainframe, minicomputer, micro-computer

Three sizes of computers. Big corporations use mainframes and large school systems might use a mid-range computer, sometimes called a minicomputer, as a file server and administrative tool. The correct term for microcomputer is personal computer or PC.


Megabytes. 1,048,576 bytes, often used to mean one million bytes (1,000,000) bytes.


The material used to support the transmission of data. This can be copper wire, coaxial cable, optical fiber, or electromagnetic wave as in microwave.


A device or medium that serves for temporary storage of programs and data during program execution. The term is synonymous with storage, although it is most frequently used for referring to the internal storage of a computer that can be directly addressed by operating instructions. Your computer's temporary storage capacity, measured in kilobytes (KB) or megabytes (MB) of RAM (random-access memory). Long-term data storage on discs, is also measured in kilobytes or megabytes.


A displayed list of options from which a choice can be made. The list is often displayed with a code opposite each option; the selection may be made by typing the appropriate code.


E-Mail: The unit of information transferred by an e-mail system. It consists of an envelope that identifies the recipients; headers containing who the message is from, to, subject, relaying information, etc; and a body that contains the information the sender wishes to communicate.


A computer system in which the central processing unit is built as a single tiny semiconductor chip or as a small number of chips.


Main computer chip that provides speed and capabilities of the computer. Also called CPU.


Bandwidth ranging above one gigahertz, used for high-speed data transmission.


Short for MOdulation/DEModulation, it is a device that can convert a digital bit stream into an analog signal (modulation) and can convert incoming analog signals back into digital signals (demodulation). The analog communications channel is typically a telephone line and the analog signals are typically sounds.

modem setup

Modem speed or baud rate, parity, data bits, stop bits, and duplex must be set the same at the user's computer as at the network system. Communication software is used to set up the modem.


A logically self-contained and discrete part of a larger computer program.


A television-like screen that shows text, graphics, and other functions performed by the computer.


An Internet-based, global hypermedia browser that provides a unified interface to the various protocols, data formats, and information archives (i.e. gopher) used on the Internet and enables powerful new ways for discovering, using, viewing, and sharing information. It was developed by NCSA as part of the WWW project.


A device that is moved by hand to move a pointer to indicate a precise position on a display screen. The device has one or more buttons on top and a cable connected to a computer; it may use wheels and be friction-driven or it may use light reflected from a special pad.


A single work assembled using elements from more than one medium, such as high-resolution color images, sounds, video, and text that contains characters in multiple fonts and styles.

multimedia mail

Provides the capability to compose, send and read messages that include things such as spreadsheets, line drawings, animated graphics, high-resolution color images, digitized speech, video, and WYSIWYG text that may contain characters in multiple fonts and styles, etc.


A device that merges information from multiple input channels to a single output channel.


The capability of some computer systems to provide access to many simultaneous users.

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