This, obviously, allows you to choose which drum rhythm to play, but also allows you to program your own rhythms from the different voices illustrated on each button. You can also program in a sequence of rhythm patterns to be played (so-many measures of “Rock I”, then swap to “Rock II”, for so-many measures, etc.). There's some variations on the patterns, you can add some extra percussion instruments, and there's a couple of awful drum intros/solos.