Mostly contemporary (rock, funk, dance, Latin, etc.). The stuff has to be moving, exciting, and even danceable. People need to hear music with a strong pulse, very preferably in 4/4 time. Strong beats to place hit points are on beats 1&3, and 2&4 (sorry if I digress musically). Up-beat eighth notes (half beats between 1, 2, 3, and 4) sometimes are tough to remember, as are hits on downbeats if they end up in contrary patterns (i.e. a repeating 3 beat pattern in 4/4 time). Even though there's a video tape to demonstrate the performance, I had to make sure that those hit points that are tough to feel or remember have subtle musical cues (i.e. 2 or 3 notes in a strong bass line, a short drum fill, etc.) that lead into or set up the 'hit', so after a few viewings you start to learn quickly where the hit points occur. It's really very simple to learn as long as you know the pattern you're working on beforehand. In fact, that's essential. DO NOT use Kickin' Tracks videos to learn the patterns; they are used to supplement the audio CD only! Learn the techniques and patterns from your instructor, your school, or any teacher approved instructional videos or CD-ROMs.