
Programmer Bram Cohen designed the protocol in April 2001, and released the first available version on 2 July 2001. BitTorrent trackers provide a list of files available for transfer and allow the client to find peer users, known as "seeds", who may transfer the files. Popular clients include μTorrent, Xunlei Thunder, Transmission, qBittorrent, Vuze, Deluge, BitComet and Tixati. BitTorrent clients are available for a variety of computing platforms and operating systems, including an official client released by BitTorrent, Inc. A BitTorrent client is a computer program that implements the BitTorrent protocol. To send or receive files, users use a BitTorrent client on their Internet-connected computer.

That bit of legwork is left up to the user instead. The program won’t use any file name matching to make swarm merging smarter, although it theoretically could. This works well enough as there is very little chance two files in your torrent list would have the exact same number of bytes and not be duplicates. It looks at file sizes as a way to match files.

The way Vuze goes about this is currently rather rudimentary.

In the example, swarm merging added an extra 1MB/s to the download.

This is a completely separate torrent, but Vuze can merge the swarms together to get that main installer file faster. Using the search feature, you can discover a second swarm sharing a download of LibreOffice that includes the installer and a help package. In the example provided by Azureus, a download of LibreOffice proceeds at 1.2MB/s.
