Peer-to-peer (P2P) file sharing is a method of sharing computer files by making them available for other users to access and download onto their own computers. You store the files on your own computer. Other people can then access those files and make copies of them.
The peer-to-peer infrastructure provides a network so that you can see which files are available for download on other computers in the network. Companies that have provided file sharing networks, software, and applications include Napster, Grokster, and BitTorrent.