Radio is widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing, and other applications. They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by another antenna connected to a radio receiver. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 3,000 gigahertz (GHz). Radio is the technology of signaling and communicating using radio waves. A variety of radio antennas on Sandia Peak near Albuquerque, New Mexico, US For other uses, see Radio (disambiguation). For its use in audio distribution, see Radio broadcasting. This article is about science and technology.