What is BitTorrent?
BitTorrent is a peer-to-peer file-sharing protocol designed by Bram Cohen, and a family of of BitTorrent compatible clients (software) support this p2p protocol. BitComet is a C++ BitTorrent client running on Windows, compatibale with BitTorrent along with many enhancement.
BitTorrent is designed to facilitate file transfers among multiple peers across unreliable networks. While downloading, clients will simultaneously upload already downloaded data to other BitTorrent clients interested in that data.
The HTTP/FTP way (Problem: more customers require more bandwidth):
The BitTorrent Solution: customers help distribute content
That's the reason why bittorrent sometimes works faster than ordinary http / ftp. In order to use this technology, users need to use a BitTorrent client, and a tracker is needed to help users know about each other.
-- The graph comes from Bram Cohen's homepage
