Internet radio (also web radio, net radio, streaming radio, e-radio, online radio, webcasting) is an audio 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 streaming media, presenting listeners with a continuous stream of audio that typically cannot be paused or replayed, 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.
Internet radio services offer news, sports, talk, and various genres of music—every format that is available on traditional broadcast radio stations. Many Internet radio services are associated with a corresponding traditional (terrestrial) radio station or radio network, although low start-up and ongoing costs have allowed a substantial proliferation of independent Internet-only radio stations.
Internet radio services are usually accessible from anywhere in the world with a suitable internet connection available; one could, for example, listen to an Australian station from Europe and America. This has made internet radio particularly suited to and popular among expatriate listeners. Nevertheless, some major networks like CBS Radio, Pandora Radio, and Citadel Broadcasting (except for news/talk and sports stations) in the United States, and Chrysalis in the United Kingdom, restrict listening to in-country due to music licensing and advertising issues.