A drum machine is an electronic musical instrument designed to imitate the sound of drums or other percussion instruments. They are used in a variety of musical genres, not just purely electronic music. They are also a common necessity when session drummers are not available or desired.

Most modern drum machines are sequencers with a sample playback (rompler) or synthesizer component that specializes in the reproduction of drum timbres. Though features vary from model to model, many modern drum machines can also produce unique sounds, and allow the user to compose unique drum beats.

In 1930–32, the spectacularly innovative and hard to use Rhythmicon was realized by Leon Theremin at the request of Henry Cowell, who wanted an instrument with which to play compositions whose multiple rhythmic patterns, based on the overtone series, were far too hard to perform on existing keyboard instruments. The invention could produce sixteen different rhythms, each associated with a particular pitch, either individually or in any combination, including en masse, if desired. Received with considerable interest when it was publicly introduced in 1932, the Rhythmicon was soon set aside by Cowell and was virtually forgotten for decades. The next generation of rhythm machines played only preprogrammed rhythms such as mambo, tango, or the like. They also have other patterns like bossa nova

Roger Linn is an industrial designer, mainly of electronic drum machines, and has recently branched out into guitar effects pedals. His products have become underground hits, being used on many famous recordings. Besides being an accomplished guitarist and producer, Roger Linn is also a member of the Dead Presidents Society, a group of distinguished innovators in the field of electronic music.

In 1979, Roger Linn revolutionized the world of electronic musical instruments by designing the world's first drum machine to use digital samples, the LM-1 Drum Computer. The LM-1 was the first drum machine to use samples of a real drum kit, though Roger Linn cannot recall exactly who the session drummer was that played the hits. To further add to the mystery, an entry in the online museum of the Roger Linn Design company credits L.A. session drummer Art Wood with most of the samples. Examples of the LM-1 in use can be found on recordings by Prince, Gary Numan, and Michael Jackson. Linn Electronics released two other designs after the LM-1: the LinnDrum and Linn 9000, which became synonymous with the music of the 1980s.