Beat snapping (often simply snapping) refers to a hit object's position on the hit object timeline in the beatmap editor. Changing the beat snap divisor allows hit objects to attach to different ticks when moved in the timeline.
The concept of snapping is based on the common principles of musical quantisation and music structure. According to them, notes in most songs have predictable positions, which are based on the lengths of fractions of a single beat. By using proper beat division, which may vary throughout a song, mappers align hit objects with the notes of a musical piece.
While the beatmap editor supports beat divisions most frequently occurring in music, an extremely small number of songs may use obscure beat patterns. In such cases, mappers should manually calculate the intervals for hit object placement.1