Upbeat

In music and music theory, the beat is the basic unit of time, the pulse (regularly repeating event), of the mensural level (or beat level). The beat is often defined as the rhythm listeners would tap their toes to when listening to a piece of music, or the numbers a musician counts while performing, though in practice this may be technically incorrect (often the first multiple level). In popular use, beat can refer to a variety of related concepts including: tempo, meter, specific rhythms, and groove.

Rhythm in music is characterized by a repeating sequence of stressed and unstressed beats (often called "strong" and "weak") and divided into bars organized by time signature and tempo indications.

Metric levels faster than the beat level are division levels, and slower levels are multiple levels. Beat has always been an important part of music. Some music genres such as disco will in general de-emphasize the beat, while other such as funk emphasize the beat to accompany dance.

The downbeat is the first beat of the bar, i.e. number 1. The upbeat is the last beat in the previous bar which immediately precedes, and hence anticipates, the downbeat. Both terms correspond to the direction taken by the hand of a conductor.

An anticipatory note or succession of notes occurring before the first barline of a piece is sometimes referred to as an upbeat figure, section or phrase. Alternative expressions include "pickup" and "anacrusis" (the latter ultimately from Greek ana ["up towards"] and krousis ["strike"/"impact"] through French anacrouse). The latter term was borrowed from the field of poetry, in which it refers to one or more unstressed extrametrical syllables at the beginning of a line.

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