File sharing is a way of making files available to other users for download over the Internet and smaller networks. It is one of the original applications on the Internet, preceding even email.
The majority of file sharing today usually involves the exchange of files over peer-to-peer (P2P) file sharing networks, where the files are stored on and served by personal computers of the users. In this section, we take a look at some of the most popular P2P file sharing programs.