A type of electronic dance music commonly called techno is the short answer. Techno is often used as a catch-all term; in actuality a wide variety of music is played at raves.Someone entirely unfamiliar with techno can be told that the music played at raves is essentially a derivative of disco, incorp orating many other influences, from Kraftwerk to hip-hop and reggae.In 1987-88, when raves began, techno was still a fairly new word being used to describe the Kraftwerk and Parliament/Funkadelic-influenced music produced by a handful of African Americans in Detroit's club circuit. The style was warmer and more soulful t han most techno we hear today, but colder and more electronic than the rhythm & blues sounds that were popular in the mainstream at the time. While early techno was probably in some DJs' playlists, the music of raves in 1987-88, according to dance music magazine articles from 1991-92, was primarily a mixture of psychedelic dance rock (the Sound of Manchester: The Happy Mondays, The Stone Roses) and Acid House (the club sound of Chicago at that time, which for some reason was very popular in England). The indie dance rock sound went out the door rather quickly. More and more styles of electronic dance music succeeded acid house, evolving for better or worse into the myriad of styles commonly referred to as "techno."
Be aware that the techno music played at raves is very rarely anything like the kind of "techno," "techno-rave," "techno-industrial," "techno-dance,"or "Eurodance" music played on mainstream or even alternative radio stations. The people making and promoting that kind of music are using techno and rave as buzzwords --a marketing tool-- and they are about as authentic as Taco Bell. Some commercially successful tunes do begin life as popular hits at raves, but by the time they hit the radio they have be en played out, killed off, buried, dug up, killed and buried again by the rave community.People who go to raves generally don't expect to hear anything that they would hear on a mainstream radio broadcast.When pop songs with techno influences emerge, ravers and musicians quickly distance themselves from it and underground techno that sounds like it, so in its own way, mainstream "techno" helps speed the development of "real"techno.
In general, the purpose of the music played at raves is to make people dance. But it is more than that: the music has to take people to another place, it has to lull the conscious mind while at the same time stimulating the subconsious as well as the bo dy. Most, but not all, music played at raves is intended to lose yourself in. Techno played at raves is a faceless, nameless organism, free of the chains of pop song structure and major label hype. It may have a hook, but no chorus. It may have a voice, but no lyric.Time stops when the mind's clock of frequent distractions is disconnected by the surreal, hypnotic syncopated rhythms being woven around your head by the DJ on the decks. Time stops and the Vibe begins.