A drum machine is an electronic musical instrument that creates percussion sounds, drum beats, and patterns. Drum machines may imitate drum kits or other percussion instruments, or produce unique sounds, such as synthesized electronic tones. Most modern drum machines allow users to program their own rhythms and beats. Drum machines may create sounds using analog synthesis or play prerecorded samples. Some drum machines have buttons or pads that allow the performer to play drum sounds “live”, either on top of a programmed drum beat or as a standalone performance. Drum machines have a range of capabilities, which go from playing a short beat pattern in a loop, to being able to program or record complex song arrangements with changes of meter and style.