Internet Radio

Internet radio (also known as web radio, net radio, streaming radio and e-radio) is an audio broadcasting service transmitted via the Internet. Broadcasting on the Internet is usually referred to as webcasting since it is not transmitted broadly through wireless means. Internet radio involves a streaming medium that presents listeners with a continuous "stream" of audio over which they have no control, much like traditional broadcast media; in this respect, it is distinct from "on-demand" file serving. Internet radio is also distinct from podcasting, which involves downloading rather than streaming. Many Internet radio "stations" are associated with a corresponding traditional (or "terrestrial") radio station or radio network. Internet-only radio stations are independent of such associations.

Internet radio services are usually accessible from anywhere in the world—for example, one could listen to an Australian station from Europe or America. Some major networks like Clear Channel in the US and Chrysalis in the UK restrict listening to in country because of music licensing and advertising concerns. Internet radio remains popular among expatriates and listeners with interests that are often not adequately served by local radio stations (such as progressive rock, ambient music, folk music, classical music, and stand-up comedy). Internet radio services offer news, sports, talk, and various genres of music—every format that is available on traditional radio stations.

Internet radio technology

Streaming

The most common way to distribute Internet radio is via streaming technology using a lossy audio codec. Popular streaming audio formats include MP3, Ogg Vorbis, Windows Media Audio, RealAudio and HE-AAC (sometimes called aacPlus). The bits are "streamed" (transported) over the network in TCP or UDP packets, then reassembled and played within seconds. (The delay is referred to as lag time.)

source : www.wikipedia.com