Two taps (a grace note followed by a full volume tap) played very close together in order to sound like one slightly longer note. In the Hudson Music DVD "Great Hands For a Lifetime", drummer and educator Tommy Igoe describes flams as "the easiest rudiment to play wrong" and goes on to say "...think of the syllable 'lam'. It's one syllable. 'Flam' is still only one syllable, but it's slightly longer." This is a good way for a beginner to conceptualize a "correct" flam.