The Roland TR-808 Rhythm Composer was one of the first programmable drum machines ("TR" serving as an initialism for Transistor Rhythm). Introduced by the Roland Corporation in early 1980, it was originally manufactured for use as a tool for studio musicians to create demos. Like earlier Roland drum machines, it does not sound very much like a real drum kit.

In the mid-to-late 1980s, after the TR-808 was discontinued, its sound again became popular, in part due to its kick drum sound, which could produce a very deep sub-bass. By the end of the 1980s, the TR-808 was popular within electronic music and hip-hop genres. As with many analogue electronic musical instruments, a great deal of effort has been put into sampling the sounds of the TR-808 for use in modern devices; however, due to the nature of analog circuitry, the result is often considered unsatisfactory and can sound unduly static and digital. Demand for the real 808 sound is so great that street prices for a used TR-808 have stayed close to what the cost of a new TR-808 was upon its initial release in 1980 when adjusted for inflation.

The sounds of the TR-808 were and still are very often used in drum and bass, hip hop, R&B, house, electro, and many forms of electronic dance music, albeit often unrecognizable after extensive processing. One method is to lower the pitch of the kick drum to near-sub-harmonic levels, as in Miami bass music, which can damage speakers.

The popularity of the TR-808 has led to many artists referring to the machine in their lyrics, and the group 808 State even named itself after the venerable machine, although Graham Massey recently admitted that up until the late 1980s he and the other members of 808 State thought the Roland TR-808 was "severely uncool".