BitTorrent is a peer-to-peer file sharing protocol designed by Bram Cohen and initally released to the public in 2001. The Bittorrent protocol itself is maintained BitTorrent, Inc which is company now owned by Cohen.
The BitTorrent protocol has become that popular around the world it is often reported to represent about 30% of all internet traffic during the day and as much as 70% of all internet traffic during the night.
BitTorrent puts such a load on internet connections that it is often considered responsible increasing the takeup of broadband throughout the world. Conversly the popularity of the bittorrent protocol is often cause for Internet Service Providers to attempt to slow down, shape and even in some cases, block BitTorrent traffic.
The initial user distributing the file creates a BitTorrent file based upon the actual file or files to be shared. They then upload that BitTorrent file to a BitTorrent site such as Mininova. These files are very small which is why some sites have hundreds of thousands and even millions of BitTorrent files for you to select from.
BitTorrent Seeds
A bittorrent seed is someone who has the full copy of any file and no longer needs to download any part of the subject file yet they continue to share the file using the BitTorrent protocol.
The initial distributor of the original file is the first seed but anybody who has downloaded the whole file then becomes a seeder of the file. The higher the number of seeds often the faster you will be able to download the file.
BitTorrent Leechers
Each peer who is in the process of downloading the file is considered to be a leecher. Other than the originator of the file, every seeder has been a leecher at one point in time. because of the way the BitTorrent protocol works. Too many leechers connected will ensure slow download speeds so the ratio between the number of seeds and leechers is often a good indicator of the health of the download.