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The transmission of words, sounds, images, or data in the form of electronic or electromagnetic signals or impulses. Transmission media include the telephone (using wire or optical cable), radio, television, microwave, and satellite. Data communication, the fastes ....

Middle of Essay
.... as printers (see Computer; Office Systems). The transmission line used can be a normal or a specially purchased telephone line called a leased, or private, line (see Telephone). It can also take the form of a microwave or a communications-satellite linkage, or some combination of any of these various systems. Hardware and Software Each telecommunications device uses hardware, which connects a device to the transmission line; and software, which makes it possible for a device to transmit information through the line. Hardware Hardware usually consists of a transmitter and a cable interface, or, if the telephone is used as a transmission line, a m ....