"Silence" is a song by Canadian electronic music group Delerium featuring Canadian singer and co-writer Sarah McLachlan. Over the years, it has been hailed as one of the greatest trance songs of all time, over a decade after its initial release. The Tiësto remix of the song was voted by Mixmag readers as the 12th greatest dance record of all time.

The original album version and subsequent radio edit of the song had a much slower tempo than the more well-known remixes and was essentially structured like a pop song, with the characteristic synthetic instrumentation of the more melodic side of ambient music — though including darker overtones, such as the prominently featured Gregorian chant (Gloria in Excelsis Deo). This last element often invites comparison to popular ambient/new age/world music projects of the 1990s like Enigma and Deep Forest who routinely sample chants from various ethnicities worldwide, though in contrast such vocals featured on Karma were all original recordings.

Although the original song did receive Canadian radio airplay in 1997, it was not released as a single until 1999, two years after the release of Karma, though it was only the Airscape Remix which received airplay at this time, rather than the more downtempo original version. The single prominently included remixes by DJ Tiësto, and Fade, which significantly boosted the song's proliferation through club play (particularly by influential DJs such as Paul Oakenfold) as evidenced by the single's positions on the Billboard Hot Dance Music/Club Play charts. It was on the soundtrack for the movie Brokedown Palace featuring Claire Danes and Kate Beckinsale.

...
Wikipedia