It has been a couple of years now that downloading became very popular on internet. If you remember Napster well, who started definitively the era of free downloading, there has been quite a road walked since then!
In fact, nowadays, almost everthing works with torrents, these external link who puts nobody in danger and who let people download for free the files of other users.
There are several torrents websites like Torrentspy, Mininova, The Pirate Bay and newly, the site who has the upperhand Meganova; almost the same as Mininova research site.
How does these sites work? You need to download a program that let you associate external links to files (Bittorrent program). After, you just need to go on websites like "Meganova torrents" and look for the file you need. A simple click and the download starts. Is it not marvelous?
Of course , not every files are copyrighted. Be sure that those are not protected by the copyrighted laws!