- physics: beat is the perception of the sum of two close frequencies as one frequency that oscillates between zero intensity and full intensity, caused by the alternating constructive and destructive interference. Beating is heard as a pulsation in loudness of two close frequencies, and , at the rate of . Thus at the unison and as the difference between and increases, the speed decreases till beyond a certain proximity beating stops and a roughness is heard instead, after which the two pitches are perceived as separate. The composer Alvin Lucier has written many pieces which feature interference beats as their main focus. Musicians may used interferance beats to objectively check tuning at the unison or other simple intervalss.
- music: beat (music) is any of the periodic transient signals in music that mark the rhythm.
- literature: beat is a genre of literature written by beatniks. See: beat generation.
- poetry: beat is sometimes used to refer to metrical feet.
- police: beat is the territory and time that a police officer patrols.
- musical genre: beat style played in the 1960s