Did you know there are several kinds of fist pumps? Mike "The Situation" Sorrentino has helpfully defined -- and illustrated -- them in his new book 'Here's the Situation'. And on 'Late Night' (weeknights, 12:37AM ET on NBC), he gave Jimmy Fallon a tutorial.

The host showed the book's illustrations of "The Overhead (aka classic pump)", "The Flatliner" and "The Downward Pump". Then (accompanied by The Roots), The Situation demonstrated how to incorporate each pump into one's clubbing routine. Fallon practiced his moves, and the GTL guru concluded, "Usually you go on back to the hotel at that point."