Yes

Yes is an English progressive rock band formed in London in 1968 and generally regarded as one of the archetypal bands of the genre. Despite a great many lineup changes, occasional splits within the group and the ever-changing trends in popular music, the band has continued on for over forty years and still retains a large following.

The band's music blends symphonic and other 'classical' structures with their own brand of rock music, which is marked by sharp dynamic contrasts, extended song lengths, abstract lyrics, and a general showcasing of instrumental prowess. Although the band's sole consistent member has been bass player Chris Squire (noted for his highly melodic and discursive playing as well as his early use of electronic effects), Yes is also generally noted for the distinctive high-register vocals of lead singer Jon Anderson and the eclectic musical stylings of a succession of guitarists (Peter Banks, Steve Howe, Trevor Rabin, Billy Sherwood), keyboard players (Tony Kaye, Rick Wakeman, Patrick Moraz, Geoff Downes, Igor Khoroshev) and drummers (Bill Bruford and Alan White). Several band members became celebrated musicians and/or bandleaders in their own right, and a 1980 lineup of the band was briefly fronted by future production star Trevor Horn.

Long-term band members Squire, Howe and White have most recently been touring (on the In The Present Tour of late 2008 and early 2009) with a Yes lineup featuring vocalist Benoit David and keyboardist Oliver Wakeman.

From Wikipedia