Choose Wha!?

[TheShootah]

Can someone explain this choose business to me, like C(50,2) or something like that, with an example. I know a good deal about simple probability from AP Stats, but I was looking at a good inclusion - exclusion post and don't really know how to work out the C(50,2) Obviously it's 50 choose 2 and that is the probability of being dealt a specific hand or something, but I dunno really how to do it, unless it's just (2 / 52) * (1 / 51), which might work. I dunno. I have no idea. Thanks....