Radio

The radio is the transmission of signals, by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels through oscillating electromagnetic fields that pass through the air and the vacuum of space. The information is routinely carried by the changes (modulation), some owned by the waves radiated such as amplitude, frequency or phase. When the radio waves from an electrical conductor, the oscillating fields induce an alternating current to the driver. This can be detected and converted into sound or other signals that carry information.