There was a time when it was quite easy to define radio. In those days radio meant wireless transmission of electromagnetic waves. Such waves were transmitted below the visible lights. For a layman, it was listening voices from remote corners of the globe without any problem of geographical barriers. In a more elite group of listeners it meant AM or FM broadcasting. Since neither the TV nor the Internet had made such rapid progress in those days, there was also no concept of free internet radio.

However, the concept of free radio stations was gradually taking a formation in the minds of the listeners. People all around the world felt quite perturbed at the regular disturbances of the intervening ads and commercials breaking the chain of listening and pleasures of enjoying such programs. 

Today, you do not require a radio set to listen to the radio programs. You can listen to the free online music and other programs quite conveniently from the radio stations on the internet that are constantly broadcasting such programs for the benefit of listeners all over the world. The program is transmitted using the satellite radio using the Satellite Digital Audio Radio Services (SDARS). There are hundreds of live internet radio stations functioning on the web and the best part of it is that the quality of transmission is much better than the traditional radio transmissions.