BitTorrent

BitTorrent is a distributed, peer-to-peer file sharing protocol which allows software and other digital media to be distributed without a central site by any user with a BitTorrent client. Although BitTorrent is often cited with cases of copyright infringement, it is a perfectly legal, legitimate and very useful protocol. Using BitTorrent significantly decreases the load on web servers, and is the preferred way of downloading a GNU/Linux distro.