These are the 40 essential rudiments that every drummer should know. Rudiments are a group of patterns that help build up muscle memory for drummers to do such things as flams, drum-rolls, etc.. There are more than 40 rudiments but these 40 are the top ones that every drummer should already know. The most common rudiments that are practiced out of the bunch are the double stroke roll, the flam, and the paradiddle.