Deep Purple are an English rock band formed in London in 1968. They are considered to be among the pioneers of heavy metal and modern hard rock, although their musical style has varied throughout their career. Originally formed as a psychedelic rock and progressive rock band, they shifted to a heavier sound with their 1970 album Deep Purple in Rock. Deep Purple, together with Led Zeppelin and Black Sabbath, have been referred to as the "unholy trinity of British hard rock and heavy metal in the early to mid-seventies". Listed in the 1975 Guinness Book of World Records as "the globe's loudest band" for a 1972 concert at London's Rainbow Theatre, they have sold over 100 million records worldwide.

Deep Purple have had several line-up changes and were broken up for eight years from 1976 to 1984, with drummer Ian Paice being the band's only constant member. The first four line-ups, which constituted the band's original 1968–1976 run, are officially indicated as Mark I (1968–1969), Mark II (1969–1973), Mark III (1973–1975) and Mark IV (1975–1976). Mark I comprised the founding members of Deep Purple, Ritchie Blackmore (guitar), Rod Evans (vocals), Jon Lord (keyboards), Ian Paice (drums) and Nick Simper (bass), while Mark II was the most commercially successful line-up, with Ian Gillan and Roger Glover replacing Evans and Simper respectively. Mark III saw David Coverdale and Glenn Hughes replace Gillan and Glover respectively, while Mark IV featured Tommy Bolin replacing Blackmore. The band split in July 1976, and Bolin died from a drug overdose five months later. Deep Purple reformed in 1984 with the Mark II line-up, which remained in place until Joe Lynn Turner replaced Gillan in 1989. Gillan rejoined in 1992, with Blackmore leaving for the second and final time the following year. He was replaced temporarily by Joe Satriani and then permanently by Steve Morse. In 2002, Lord retired and was replaced by Don Airey, which saw Deep Purple settle into its longest running line-up, unchanged for the next twenty years, until Morse announced his departure from the band in 2022. His place was taken by Simon McBride. Paice, Glover, Gillan, Airey and McBride comprise the current line-up of Deep Purple.

Deep Purple were ranked number 22 on VH1's Greatest Artists of Hard Rock programme, and a poll on radio station Planet Rock ranked them 5th among the "most influential bands ever". The band received the Legend Award at the 2008 World Music Awards. Deep Purple (specifically Blackmore, Lord, Paice, Gillan, Glover, Coverdale, Evans, and Hughes) were inducted into the Rock and Roll Hall of Fame in 2016.