Radio: A Form of Communication Radio is a form of communication in which intelligence is transmitted without wires from one point to another by means of electromagnetic waves. Early forms of communication over great distances were the telephone and the telegraph. They required wires between the sender and receiver. Radio, on the other hand, requires no such physical connection. It relies on the radiation of energy from a transmitting antenna in the form of radio waves. These radio waves, traveling at the speed of light (300,000 km/sec; 186,000 mi/sec), carry the information. When the waves arrive at a receiving