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Technology Terminologies

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Basic component of communication over a network. A group of bits of fixed maximum size and well-defined format that is switched and transmitted as a complete whole through a network. It contains source and destination address, data and control information. See also frame.


A variable, or quantity that can assume any of a given set of values, of which there are two kinds: formal and actual. (See argument.)


Data has even or odd parity if the number of 1 bits is even or odd. A parity bit is a bit added to data to make the parity always even or odd. A parity bit may be used for detection of errors in RAM as well as in data transmitted through noisy communications channels. A parity error is detected when data that is supposed to be even parity is not, or vice versa.


A string of characters that a program, computer operator, or user must supply to meet security requirements before gaining access.


Anything extra or added on for your computer, such as a modem, a mouse, or a fax adapter. Peripherals can be added on externally or installed inside the machine.


Personal Computer. An IBM or IBM clone personal computer (Microcomputer) that is used by one person, as opposed to a Macintosh.


Packet Internet Groper. Probably originally contrived to match the submariners term for a sonar pulse.
n. Slang term for a small network message (ICMP ECHO) sent by a computer to check for the presence and aliveness of another.
v. To verify the presence of. To get the attention of.


Picture Element. In computer graphics, the smallest element of a display space that can be independently assigned color or intensity.


Hardware environment that supports the running of a computer system.


An output device for translating information from a computer into pictorial or graphical form on paper or a similar medium.


That portion of a computer through which a peripheral device may communicate. Often identified with the various plug-in jacks on the back of your computer. On a network hub, it is the connector that receives the wire link from a node.


In computer usage, a file or program is "portable" if it can be used by a variety of software on a variety of hardware platforms. Numeric data files written as plain character format files are fairly portable.


The act of placing a message in an on-line conference. The noun "posting" is sometimes used to refer to a conference message.


A language defined by Adobe Systems, Inc. for describing how to create an image on a page. The description is independent of the resolution of the device that will actually create the image. It includes a technology for defining the shape of a font and creating a raster image at many different resolutions and sizes.

Power PC

A RISC CPU chip designed by IBM and Apple and manufactured by Motorola. It features a 32/64 bit implementation and full binary compatibility with the IBM RS/6000. Four models are planned: 601, 603, 604,and 620. The 601 borrows its basic architecture from the Model 200 RS/6000. It adopts the internal bus structure of the Motorola 88100 and the construction plans from the 0.5 micron chip fabrication techniques used by the Model 970 RS/6000. The 603 is an entry-level device targeted toward embedded applications and low power consumption uses such as notebooks and low-end workstations. The 604 is a second-generation version of the 601.


An output device that converts the coded information from the processor into a readable form on paper.


The printed output of a computer.


A portion of a high-level language program that performs a specific task.


A systematic sequence of operations to produce a specified result; a unique, finite course of events defined by its purpose or by its effect and achieved under given conditions. As a verb, to perform operations on data in a process. Also an address space and the code executing in it.


A set of actions or instructions that a machine is capable of interpreting and executing. Used as a verb, to design, write and test such instructions.


A person who designs, write and tests computer programs.


A notation for the precise description of computer programs or algorithms. Programming language languages are artificial languages in which the syntax and semantics are strictly defined.


A character or message provided by an operating system or program to indicate that it is ready to accept input.


An agreement that governs the procedures used to exchange information between cooperating entities and usually includes how much information is to be sent, how often it is sent, how to recover from transmission errors and who is to receive the information.

public domain

Not protected by copyright; you may freely make copies and distribute them; you may make derivative works.

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