Radio waves are a type of radiation. Radiation is energy that moves. Like all waves of radiation, radio waves have a property called frequency. Frequency describes the number of waves that pass a given point each second.
Radio waves are sent out by a device called a transmitter. The transmitter turns talking, music, pictures, or other information into electric signals. The transmitter combines these electric signals with radio waves of a certain frequency. The waves spread out in all directions from an antenna connected to the transmitter.
The radio waves are picked up by an antenna connected to a device called a receiver. The receiver separates the electric signals from the radio waves. Then it turns the electric signal back into the original sounds or pictures. A receiver that picks up waves that carry sound is called a radio. A radio sends the electric signal through speakers so the sound can be heard. Each radio station sends out radio waves of a certain frequency. A person changes a radio from one frequency to another to hear different stations.
