An English electronic group, and principal name under which duo Karl Hyde and Rick Smith have recorded together since 1980. The band is perhaps best known for Born Slippy, a track made popular in the hit 1996 Danny Boyle film Trainspotting.

Hyde and Smith began their musical partnership with the Kraftwerk and reggae-inspired sounds of the Screen Gemz while working together in a diner in the city of Cardiff, where both had been studying. In 1983, they recorded two albums for CBS Records with a proto-electroclash new romantic band whose name was a graphic squiggle, which was soon given a pronunciation, Freur.

Freur disbanded in 1986. In 1987, members of Freur created the band Underworld and tried a more guitar-oriented funky electropop sound on Underneath the Radar and Change the Weather for Sire Records before disbanding in 1990.

After a short break, Hyde and Smith recruited Essex DJ Darren Emerson and, after several minor releases and remixes as Lemon Interupt and Steppin' Razor, readopted the Underworld name and produced danceable techno as a trio.

The addition of Emerson completed Underworld's techno/rock fusion and moderated some of the poppier elements in the original duo's work. Their first album, dubnobasswithmyheadman, was considered more accessible than the group's earlier material and crossed a large spectrum of dance music. The material often included whispered lyrics from Hyde, mixing conventional songwriting with the use of found material from overheard conversations, answering machine recordings and the like.

The band's 1996 album, Second Toughest In The Infants, was their second studio album with Emerson and achieved a degree of commercial success, due in part to its release coinciding with that of the film Trainspotting (although Born Slippy did not appear on the album).

After the release of their fifth studio album Beaucoup Fish in 1999, Underworld embarked on a spirited and well-received tour, which resulted in a live CD and DVD drawn from several dates on the tour. Called Everything, Everything, the project captured the live Underworld experience very faithfully.

In 2002, Emerson decided to leave Underworld to focus on his solo projects and record label. Hyde and Smith decided to continue, once again, as a duo. They recorded a new album, A Hundred Days Off, which was generally well-received.

While touring in 2005, the duo was joined on stage by Darren Price, a DJ and producer well known by the band who had remixed Underworld releases in the past.

Underworld's seventh studio album, Oblivion with Bells, was released in 2007.