What is BitTorrent

BitTorrent is a type of Peer-to-Peer (WhatIs.P2P) technology. It is generally considered to be one of the more sophisticated and reliable WhatIs.P2P technologies as it has some advantages of 'standard' P2P.

The standard way to use a P2P network follows these steps: 

1. open your file sharing program
   
2. search the WhatIs.P2P network for a particular file using the file sharing program
   
3. request a file to download
   
4. if all is well the other computer then delivers a file to your computer
   

With BitTorrent the process is (generally) slightly different. It follows these steps:

1. open a browser and search torrent networks for a file
2. download a torrent file corresponding to the file you were searching for
3. open the torrent file in your BitTorrent software
4. the file you want is then delivered from multiple clients on the BitTorrent network

The BitTorrent process may sound a little more complex (it is) however it has some advantages over other types of WhatIs.P2P networks. The most notable advantage is that your download is not reliant on one source. You can draw the same file from multiple computers, and the BitTorrent software will manage problems by swapping and choosing download sources. This reduces your dependence on the original download source and can produce very fast download speeds.  

What is a Torrent? 

A torrent (sometimes called 'torrent file' but most commonly just referred to as a 'torrent') is a text file that contains information on the file you want to download. It is a text file that ends with the suffix '.torrent'. You download this file directly from the internet through your browser. The torrent is very small and it contains some general information about the file you are looking for. The torrent also contains a unique code ('unique identifier') referencing the actual file you wish to download. No other file will be associated with this identifier.

When you have downloaded a Torrent you must open it with your BitTorrent software (also known as a 'BitTorrent client'). The software then connects to a server known as a BitTorrent Tracker. There are many trackers on the internet, and when your software contacts a tracker (the tracker location is identified within the torrent file) it sends the tracker the information in the torrent. The Tracker then responds by telling your BitTorrent client where it can start downloading the file you want.

What is a Seed?

As stated earlier, BitTorrent downloads small pieces of the file you want from multiple sources (computers on the BitTorrent network). BitTorrent only starts the downloads from computers that have the complete file available for download. These sources are known as seeds. If there are 20 users on the BitTorrent Network that have a complete copy of the file you want, then the tracker will list each of these 20 seeds and start downloading from them.

Some seeds are better than others of course because some users have faster internet connections and machines. BitTorrent tries to connect you with the best ones so your download will be as quick as possible.

How do I share a file on BitTorrent?

To share a new file (one which you have not just downloaded through a torrent) you have to first create a torrent for the file, and then register it with a tracker. You must then run the BitTorrent client with the newly created torrent open until others have also downloaded the file and share it by becoming seeds.