radio waves

electromagnetic waves which transmit sounds or signals through space without wires to a receiving set

Radio waves are  electromagnetic waves occurring on the radio frequency portion of the electromagnetic spectrum. A common use is to transport information through the atmosphere or outer space without wires. Radio waves are distinguished from other kinds of electromagnetic waves by their wavelength, a relatively long wavelength in the electromagnetic spectrum.
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Radio frequency, or RF, is a frequency or rate of oscillation within the range of about 3 Hz and 300 GHz. This range corresponds to frequency of alternating current electrical signals used to produce and detect radio waves. Since most of this range is beyond the vibration rate that most mechanical systems can respond to, RF usually refers to oscillations in electrical circuits.
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Radio waves Electromagnetic energy of the frequency range corresponding to that used in radio communications, usually 10,000 cycles per second to [more]Radio waves - Community and Resources

Electromagnetic Waves with a Wavelength of approximately 3 kilometers to 30 centimeters.

Electromagnetic radiation with a wavelength which is greater than one metre, and in practice, up to many kilometres. This is the least energetic form of electromagnetic radiation.