Ambient music evolved from the experimental electronic music of '70s synth-based artists like Brian Eno and Kraftwerk, and the trance-like techno dance music of the '80s. Ambient is a spacious, electronic music that is concerned with sonic texture, not songwriting or composing. It's frequently repetitive and it all sounds the same to the casual listener, even though there are quite significant differences between the artists. Ambient became a popular cult music in the early '90s, thanks to ambient-techno artists like the Orb and Aphex Twin.
Coined by the Beyond label for its compilation series of the same name, Ambient Dub has since been generalized by artists, critics, and audiences alike to refer to any form of rhythmic, usually beat-oriented ambient using the tastes, textures, and techniques of Jamaican dub-style production (e.g. reverb, emphasis on bass and percussion, heavy use of effects). Although the term has fallen out of favor due to the fevered intermingling of styles characteristic of post-rave electronica, it remains useful in demarcating the denser, more electronic applications of dub from the more hip-hop derived styles of downtempo, atmospheric beat music. Artists include the Orb, Higher Intelligence Agency, Sub Dub, Techno Animal, Automaton, and Solar Quest.
Yet another in a long line of plastic placeholders to attach itself to one arm or another of the U.K. post-acid house dance scene's rapidly mutating experimental underground, Trip-Hop was coined by the English music press in an attempt to characterize a new style of downtempo, jazz-, funk-, and soul-inflected experimental breakbeat music which began to emerge around in 1993 in association with labels such as Mo'Wax, Ninja Tune, Cup of Tea, and Wall of Sound. Similar to (though largely vocal-less) American hip-hop in its use of sampled drum breaks, typically more experimental, and infused with a high index of ambient-leaning and apparently psychotropic atmospherics (hence "trip"), the term quickly caught on to describe everything from Portishead and Tricky, to DJ Shadow and U.N.K.L.E., to Coldcut, Wagon Christ, and Depth Charge -- much to the chagrin of many of these musicians, who saw their music largely as an extension of hip-hop proper, not a gimmicky offshoot. One of the first commercially significant hybrids of dance-based listening music to crossover to a more mainstream audience, trip-hop full-length releases routinely topped indie charts in the U.K. and, in artists such as Shadow, Tricky, Morcheeba, the Sneaker Pimps, and Massive Attack, account for a substantial portion of the first wave of "electronica" acts to reach Stateside audiences.
A suitably vague term used to describe the emergence of electronic dance music increasingly geared to listening instead of strictly dancing, Electronica was first used in the title of a series of compilations (actually called New Electronica) spotlighting original sources of Detroit techno such as Juan Atkins and Underground Resistance alongside European artists who had gained much from the Motor City's futuristic vision for techno. The word was later appropriated by the American press as an easy catch-all for practically any young artist using electronic equipment and/or instruments, but electronica serves to describe techno-based music that can be used for home listening as well as on the dance floor (since many electronica artists are club DJs as well).
The music played by a generation raised on jazz as well as funk and hip-hop, Acid Jazz used elements of all three; its existence as a percussion-heavy, primarily live music placed it closer to jazz and Afro-Cuban than any other dance style, but its insistence on keeping the groove allied it with funk, hip-hop, and dance music. The term itself first appeared in 1988 as both an American record label and the title of an English compilation series that reissued jazz-funk music from the '70s, called "rare groove" by the Brits during a major mid-'80s resurgence. A variety of acid jazz artists emerged during the late '80s and early '90s: live bands such as Stereo MC's, James Taylor Quartet, the Brand New Heavies, Groove Collective, Galliano, and Jamiroquai, as well as studio projects like Palm Skin Productions, Mondo Grosso, Outside, and United Future Organization.