utorrent is a free BitTorrent Client. It offers great features for nothing as it just displays ads which are annoying for some users. It is very lightweight application which do not disturb routine tasks. But if you have an older machine then you probably thinking of removing these ads to speedup a bit. If you want to remove these ads then buy pro version of utorrent, they deserve it. Or if you are cheater then i am gonna tell you a simple steps to get rid off these ads.
Torrent contains metainfo about files and folders to be distributed. Each torrent has i unique id also called torrent hash. A Software used to download files from torrent is called torrent client. A torrent client uses BitTorrent Protocol so it picks up files from different computers. This method uses very low bandwidth from each server.