What kinds of things can you legally download from thepiratebay?

Stuff that are normally free or the works of people who choose to publish their work on pirate bay such as software, pdf files,...

The term "Pirate Bay" is really irrelevant to the question. While it is true that most of the torrents they link to(movies, music, pron, etc) are copyrighted, there are literally thousands of torrents that are legal to download and distribute. There are oodles of torrent sites that work the same way, it's just that the media picks on the Pirate Bay(probably because media types are idiots, and probably just because of the word "Pirate" in the website name).

Many software developers(Ubuntu is a pretty good example) release their software on bittorrent because it saves them thousands of dollars in bandwidth costs(Why would they want everybody to download their software from the Ubuntu site(which costs lots of money), when they can release it on bittorrent and let everybody copy it from each other at no cost? Many open-source(free) software packages use this method to release software.

Many indie music artists also release their music on bittorrent just to get some exposure. The question you have to ask yourself is "Is this something I would have to pay for if I went to get it at Walmart?" If the answer is yes, then it is most probably illegal.

There are also torrent sites, like:

http://www.legittorrents.info/

that only link to legal torrents. Read this article:

http://gigaom.com/video/ten-more-sites-for-free-an...

To find more.

Well, the website is in Sweden, and copyright infringements from U.S. don't apply... but like that one guy said Ubuntu, back up stuff, etc. if you want to get technical

u can legally download opensource operating system, games demos that are free of cost maybe some pictures.

Stuff like Ubuntu, anything that you wouldn't normally pay for is fine to download there.

i dont thing you can download anything legally unless you pay for it

Nothing is legal through thepiratebay.org.

none it's all illegal depending on your country