BPM, or Beats Per Minute, is a measure of the speed at which music is played. It represents the number of beats per minute. For example, music with a BPM of 120 will have 120 beats per minute.

It is important for synchronising music with other elements, such as lighting effects or dance moves. It is also useful for DJs who need to mix two tracks together harmoniously.

There are several ways of measuring the BPM of a piece of music. The most common method is to use specialized software that analyzes the music and automatically determines the BPM. DJs also use manual techniques, such as using a metronome or hand counters.