Black Holes

have black holes actually been proven to exist? when i was a kid i was all into astronomy and recently i've been looking into it again, and after reading several articles on the subject im still kinda in the dark. if you say wiki black holes there's tons of inferential information about them existing but no references to actual known black holes. also I just read some random post on /b/ (lol, reliable information) saying "as science has proven a blackhole is impossible (NASA news 2006) " <- anyone know wtf article he's referring to.

so tl;dr, blackholes: definately out there or an interesting theory?

OP here. I didn't mean to make it sound like black holes were only some vague possibility, I was just wondering if there'd yet been any definative proof on them versus a strongly justified theory. i.e, we've directly observed supernovas, perhaps someday we'll observe the final stages of a supermassive star collapsing into a black hole.