Gnutella is a file sharing network, which allows users to exchange files such as mp3, mpeg and image files. The internal workings of Gnutella is different to the orginal Napster. Gnutella doesn't use a central command, but a system more similar to a daisy chain network. Gnutella is free for download, there are lots of file sharing programs that use Gnutella functions. Gnutella claim to be the most used file sharing network. It is estimated that Gnutella has forty percent of all file sharing users.