Rhythm

Rhythm is the difference of the accentuation of sounds or other events over time. "Rhythm involves patterns of duration that are phenomenally present in the music" with duration perceived by interonset interval. When governed by rule, it is called meter. It is intrinsic in any time-dependent medium, but it is most related with music, dance, and the majority of poetry. The study of rhythm, stress, and pitch in speech is called prosody; it is a topic in linguistics. All musicians, instrumentalists and vocalists, work with rhythm, but it is often considered the primary domain of drummers and percussionists.

In Western music, rhythms are usually arranged with respect to a time signature, partially signifying a meter. The speed of the underlying pulse, called the beat, is the tempo. The tempo is frequently measured in 'beats per minute’; 60 bpm means a speed of one beat per second. The length of the meter, or metric unit, is regularly grouped into either two or three beats, being called duple meter and triple meter, respectively. If each beat is grouped in two, it is simple meter, if in three compound meter.