The media has been throwing the word piracy around a lot lately, but what does that really mean, and what does it have to do with torrents?
Piracy is defined by Wikipedia as “Copyright infringement (or copyright violation) is the unauthorized or prohibited use of works covered by copyright law, in a way that violates one of the copyright owner's exclusive rights, such as the right to reproduce or perform the copyrighted work, or to make derivative works.” This is a long and fancy way of saying that it is the illegal copying or distribution of movies, music, games, or other copyright materials.
Torrenting rapidly became the most prevalent way to pirate materials, due to its high speed, decentralized nature, and ease of use. It was also because of these things that stopping piracy via torrent is so difficult. Its speed means that the traffic is only actually on the network for a limited time, usually much shorter than a normal download would be. Because its decentralized, simply blocking whoever started the torrent doesn't stop the rest of the people downloading it, and its easy to encrypt the traffic. The ease of use leads to its incredible widespread usage, even among people who would seldom consider themselves “Computer Savvy”.
The weak point in the torrenting infrastructure is what is know as the “Tracker”. The Tracker does what it says on the tin, keeping track of who has what data and who needs what pieces. It would be easy to put a large dent in torrent traffic by simply shutting down these trackers, but there is a legal caveat that usually prevents this from happening.
The Tracker never actually does ANYTHING illegal. It is never in possession of illegal data, nor does it in any way violate any copyright laws. Because of this, trackers live in a legal “Grey Area,” skirting around the edges of law enforcement. Many Trackers are even located out of country. A good example is The Pirate Bay, a very large and popular tracker. It's servers reside in Sweden, which has a very light stance on Copyright laws. This makes it even harder for the America based companies who frequently try and take it to court to actually make any difference.
Even this weakpoint, however, is being fixed. The next generation of Torrents will likely use a new method of tracking, one which doesn't rely on a separate tracker at all! This new technology uses other Peers, or people who are simultaneously downloading a torrent, to locate and download the pieces that are missing locally, or even using a trust relationship to find and download a whole new torrent.