Torrent

.torrent files are basically BitTorrent's equivalent to ed2k links used in eDonkey network. In essence, .torrent files include instructions for BitTorrent -compatible P2P clients where to find the "tracker" for the downloaded file, hashed checksum that verifies for the client that it is actually downloading the correct file, the full size of the file and the filename of the file.

So, essentially .torrent files are very, very small files that simply contain some textual data about the file itself. Thus, downloading the torrent file itself takes only matter of seconds, if not milliseconds, but it is not the file that is downloaded from the P2P network. Instead, .torrent files are typically hosted on just standard web servers and can be even passed via email. But in a computer with a BitTorrent -compatible client installed in it, launching a .torrent file typically starts a process where the BitTorrent -compatible client first contacts the tracker described in the .torrent file and if the tracker server is found and "seeds" (people sharing the file in question) are available, launches a download process of the file described in the .torrent file.

To use .torrent files in order to download files from BitTorrent P2P network, you need to have a BitTorrent -compatible client installed on your computer. Some of the clients are available here:

BitTorrent (the original client, open source)
ABC (open source)
Azureus (open source)
BitComet (open source)
BitTornado (open source)
G3 Torrent (open source)

If you are interested to know more about the BitTorrent, you might find these links useful:

Information about BitTorrent itself
BitTorrent FAQ
ABC guide
Azureus guide
BitComet guide
BitTornado guide
G3 Torrent guide
AfterDawn's P2P forum

Related glossary terms

Related software tools

	Azureus Java BitTorrent client for Windows 9x (Open source) Azureus is Java based BitTorrent client, with multiple torrent downloads, seeding, embedded tracker and lots more.
	BitComet (Ad-supported) BitComet is a highly versatile and powerful BitTorrent client
	BitLord (Freeware) BitLord is a p2p file-sharing program, fully compatible with Bittorrent, which is the most popular p2p protocol designed for high-speed distribution of large files.
	BitRocket for Mac OS X (Open source) BitRocket is a Native(Open Source) BitTorrent client for Mac OS X. At the heart of it's core resides the powerful libtorrent BitTorrent library.
	BitSpirit (Freeware) BitSpirit is a free BitTorrent client that has quite impressive number of features, including download queue, personalization features and much more.
	BitTornado (Open source) BitTornado is an alternative BitTorrent client that allows a bit more adjustments than the original client.
	BitTorrent (Ad-supported) BitTorrent client is an application used for downloading torrents -- specific files or directories shared by Internet users.
	BitTorrent for Linux (Open source) BitTorrent client is an application used for downloading torrents -- specific files or directories shared by Internet users.
	BitTorrent for Mac OS X (Open source) BitTorrent client is an application used for downloading torrents -- specific files or directories shared by Internet users.
	eDonkey (Windows command line) (Freeware) Command line client for eDonkey2000 peer-to-peer file sharing network.
	eDonkey for Mac OS X (Freeware) One of the best P2P file sharing applications, combines good sides from Gnutella and Napster.
	eDonkey Linux Command Line Client (Freeware) eDonkey is one of the most popular P2P sharing tools at the moment.
	eDonkey2000 Windows GUI Client (Freeware) eDonkey2000 is a new peer-to-peer file sharing application that combines the good features from both Napster and Gnutella.
	G3 Torrent (Open source) G3 Torrent is an extended BitTorrent client based on the original Python code.
	uTorrent (Ad-supported) µTorrent (aka uTorrent) is an efficient and feature rich BitTorrent client for Windows.
	Vuze (Ad-supported) Azureus is Java based BitTorrent client, with multiple torrent downloads, seeding, embedded tracker and lots more.
	Vuze (Azureus Java BitTorrent client) for Linux (Open source) Azureus is Java based BitTorrent client, with multiple torrent downloads, seeding, embedded tracker and lots more.
	Vuze for Mac OS X (Open source) Azureus is Java based BitTorrent client, with multiple torrent downloads, seeding, embedded tracker and lots more.