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CD, abbreviation for compact disc

(Encyclopedia)CD: see compact disc.

modulation, in communications

(Encyclopedia)CE5 Modulation modulation, in communications, process in which some characteristic of a wave (the carrier wave) is made to vary in accordance with an information-bearing signal wave (the modulatin...

camera

(Encyclopedia)CE5 Image formed by a camera camera, lightproof box or container, usually fitted with a lens, which gathers incoming light and concentrates it so that it can be directed toward the film (in an opt...

analog circuit

(Encyclopedia)analog circuit, electronic circuit that operates with currents and voltages that vary continuously with time and have no abrupt transitions between levels. Generally speaking, analog circuits are cont...

CD-ROM

(Encyclopedia)CD-ROM: see compact disc.

modem

(Encyclopedia)modem [modulator/demodulator], an external device or internal electronic circuitry used to transmit and receive digital data over a communications line normally used for analog signals. A modem attach...

cellular telephone

(Encyclopedia)cellular telephone or cellular radio, telecommunications system in which a portable or mobile radio transmitter and receiver, or “cellphone,” is linked via microwave radio frequencies to base tran...

computer

(Encyclopedia)CE5 Schematic diagram of a computer system: Data flow is indicated by solid lines; control signals are indicated by dashed lines. computer, device capable of performing a series of arithmetic or l...

code, in communications

(Encyclopedia)code, in communications, set of symbols and rules for their manipulation by which the symbols can be made to carry information. By this extended definition all written and spoken languages are codes. ...

personal computer

(Encyclopedia)personal computer (PC), small but powerful computer primarily used in an office or home without the need to be connected to a larger computer. PCs evolved after the development of the microprocessor m...