The types of electromagnetic waves, from low to high frequency, are: Radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays and gamma rays. This is also the order from low energy to high energy and from long wavelength to short wavelength.
Radio waves are the lowest frequency of the types of electromagnetic radiation. They're also the lowest in energy. Radio waves are sometimes called "RF" for radio frequency. They're used mainly for communication. Television, radio, radar and cell phone signals are all transported by radio waves. Communication with satellelites is also done via radio waves. This is how satellite TV and GPS information is sent. Various frequencies can be used for different forms of communication. Household devices such as television and garage door remote controls, wireless cameras, wireless routers and Bluetooth devices all use radio frequencies.
Radio frequencies are particulary useful for these purposes because there's a wide range of frequencies available and because their low energies mean that they're safe around living things.
The way radio frequency transmission works is that waves of a particular frequency are generated by an electromagnetic process. They travel at the speed of light, 3.0 x 10^8 meters per second, are received by antennas on tuners that tune in only certain wavelengths. They're converted to another type of signal, for example mechanical sound waves.
Radio waves are found all around us, but are only detected when captured with an antenna and converted to something meaningful. They range in length from about .001 meter to over 100,000 meters. In addition to artificially produced radio waves around us, there are naturally occuring radio waves that are produced by lightning and by events in space.