Bittorrent networking is the most popular form of modern P2P (peer-to-peer) file sharing. Since 2006, bittorrent sharing has been the primary means for users to trade software, music, movies, and digital books online. Torrents are very unpopular with the MPAA, the RIAA, and other copyright authorities, but are much beloved by millions of college and university students around the planet.

Bittorrents (also known as "torrents") work by downloading small bits of files from many different web sources at the same time. Torrent downloading is extremely easy to use, and outside of a few torrent search providers, torrents themselves are free of user fees.

The Pirate Bay

The Pirate Bay (commonly abbreviated TPB) is a Swedish file-sharing website founded in 2003 that hosts magnet links and that bills itself as "The world's most resilient BitTorrent site" (as of 2012, "The galaxy's most resilient ..."). The Pirate Bay is currently ranked as the 71st most visited website in the world and 12th in Sweden, according to Alexa Internet. The Pirate Bay has over five million registered users and as of May 2012 hosts over four million torrents. According to the Los Angeles Times, the Pirate Bay is "one of the world's largest facilitators of illegal downloading" and "the most visible member of a burgeoning international anti-copyright or pro-piracy movement".

Isohunt

isoHunt is a BitTorrent index with over 1.7 million torrents in its database and 20 million peers from indexed torrents. With 7.4 million unique visitors as of May 2006, isoHunt is one of the most popular BitTorrent search engines. Thousands of torrents are added to and deleted from it every day. Users of isoHunt perform over 40 million unique searches per month. On October 19, 2008, isoHunt passed the 1 petabyte mark for torrents indexed globally. The site is the third most popular BitTorrent site as of 2008. According to isoHunt, the total amount of shared content was more than 14.11 petabytes as of June 13, 2012.

Torrentz

Torrentz is a Finland-based meta-search engine for BitTorrent that is run by an individual known as Flippy. It indexes torrents from various major torrent sites such as yourBittorrent and offers compilations of various trackers per torrent that are not necessarily present in the default .torrent file, so that when a tracker is down, other trackers can do the work. It was the second most popular torrent website after The Pirate Bay in 2010, and it currently has a traffic rank of 145 on Alexa.

Torrentz was blocked starting 3 May 2012, in India under orders of the Indian Department of Telecom without any stated reasons or prior warnings. The block was enforced by a number of ISPs, including Reliance Communications, Tikona Digital Networks, Airtel, Aircel, MTNL, BSNL and Vodafone. Other ISPs however, did not enforce the block, such as You Broadband and Hathway. The ban was lifted after a few days. As of 17 May 2012 the Site has been blocked with the error message "Access to this site has been blocked as per Court Orders" It is operational as on 28-05-2012

YourBittorrent

Founded as myBittorrent in 2003, the new site yourBittorrent is the result of a split in ownership in 2009. The site is a torrent tracking website for the P2P BitTorrent network. As such it does not host files, but hosts information about the location of these files in an indexed torrent file. These torrent files are read by a client located on an individual's computer.

yourBittorrent uses automated software to search the Internet for host file information and does not actively oversee what is indexed in its database. With a lack of oversight, the site hosts some torrents which allow users to access software, movies, music and other items under which are under copyright and thus illegal to publicly distribute, though the files themselves remain on other servers. Illegal trackers are removed by the site when a request is made by a legitimate party.

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