Internet radio (also web radio, net radio, streaming radio, e-radio webcasting) is an audio service transmitted via the Internet. Music streaming 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 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. Many Internet radio services are associated with a corresponding traditional (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 CBS Radio and Citadel Broadcasting (except for news/talk and sports stations) 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 eurodance, 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.