Internet radio services are usually accessible from anywhere in the worldâfor 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.[citation needed] 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 musicâeverything that is available on traditional radio stations.
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.)
