Confusion about file sharing

[Thermal]

Are file sharing sites like megaupload/rapidshare/4shared illigal?

There terms of use really don't cover it, I assume downloading material for free would be, but it's sharing meaning it was brought even if the down loader didn't buy. If it is illegal would the downloader be doing the illegal thing or the person who put it on the site? Because I used it yesterday and Didn't even know if it was legal or not, the terms of use don't tell you, perhaps I'm gullible but I really don't know either way.


And yeah don't give me a warning if this has to be closed, I just want to know the answer, thanks...