Half-time (music) each measure (a whole note) is divided in two by the bass drum (half note), each half is divided in two by the snare drum (quarter note, collectively the bass and snare divide the measure into four), and each quarter note is divided in two by a ride pattern (eighth note). "Half"-time refers to halving this division (divide each measure into quarter notes with the ride pattern), while "double"-time refers to doubling this division (divide each measure into sixteenth notes with the ride pattern). A classic example is the half-time shuffle, a variation of a shuffle rhythm, which is used
Grace note the bar in which they are contained - and therefore, do not require other notes to be dropped from the bar to keep the time signature intact. In bagpipe music there is extensive use of grace notes. Indeed, because the chanter is not tongued but supplied by a continuous air source from the bag, grace notes are sometimes the only way to differentiate between notes. For example, inserting a grace note between two crotchets (quarter notes) played at the same pitch is the only way to indicate them as opposed to them sounding like a single minim (half note). Various