File sharing has become a widely discussed and contested topic since it first reached public awareness in the late 1990s, largely because of its central role in a number of prominent disputes surrounding copyright and Internet law and policy. It is generally associated with the unlicensed downloading of commercial music, movies, and software, but it is also a term used to describe a broader family of technologies that offer communicative affordances between peers in a digital network. This entry discusses the history of file sharing, as well as its technological, economic, legal, and social impact.