Hey, guess what? America still likes watching people party in movies. In its first weekend out, Project X — the Todd Phillips-produced epic party/found footage flick — made over $20 million, good for second place in the box office wars. It also got us thinking about the rich tradition of parties as depicted by movies. It turns out, after some heavy-duty analysis, that almost any cinematic depiction of revelry can be categorized into one of five primary movie-party groupings. These are generalizations, of course, which means not every movie party is a perfect fit for its chosen category. Some movie parties might easily fit into two or more categories; others may truly feel like sui generis creations. But as long as we don't get too bogged down in those pesky details, our five-category taxonomy is unimpeachable. So: Consult Grantland's Rough Guide to Partying in Movies, and never feel uninformed while living vicariously through fictional characters again! As a great man once said, “It's a party it's a party it's a party it's a parttty.”