Telecommunications 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 fastest growing field of telecommunication, is the process of transmitting data in digital form by wire or radio. Digital data can be generated directly in a 1/0 binary code by a computer or can be produced from a voice or visual signal by a process called encoding. A data communications network is created by interconnecting a large number of information sources