The word "radio" is derived from the Latin word "radius", meaning "spoke of a wheel, beam of light, ray". It was first … See more

See History of radio, Invention of radio, Timeline of radio, History of broadcasting
Electromagnetic waves were predicted by James Clerk Maxwell in his 1873 theory of electromagnetism, now called Maxwell's equations, … See more

Radio waves are radiated by electric charges undergoing acceleration. They are generated artificially by time varying electric currents, consisting of electrons flowing back and forth in a metal conductor called an antenna. … See more

In radio communication systems, information is carried across space using radio waves. At the sending end, the information to be sent is converted by some type of transducer to a time-varying electrical signal called … See more

The airwaves are a resource shared by many users. Two radio transmitters in the same area that attempt to transmit on the same frequency will interfere with each other, causing garbled reception, so neither transmissio… See more

Below are some of the most important uses of radio, organized by function.
Broadcasting is the one-way transmission of information from a transmitter to receivers belonging to a public audience. Since the radio wave… See more

• Radio portal
• Electromagnetic radiation and health
• Internet radio
• List of radios – List of specific models of radios… See more