From left to right: Mike Portnoy, John Petrucci, James LaBrie, John Myung, Jordan Rudess
|Origin||New York, USA|
|Genre(s)||Progressive metal, Progressive rock|
|Label(s)||Roadrunner, Elektra, EastWest, Atco, Mechanic Records|
|Associated acts||Liquid Tension Experiment, Liquid Trio Experiment, Explorers Club, MullMuzzler, Nightmare Cinema, OSI, Platypus, The Jelly Jam, Transatlantic, True Symphonic Rockestra, Chroma Key, Ayreon|
|James LaBrie |
Dream Theater is an American progressive metal band formed in 1985 under the name "Majesty" by John Myung, John Petrucci and Mike Portnoy while they attended Berklee College of Music in Boston, before they dropped out to support the band. Though a number of lineup changes followed, the three original members remain today along with James LaBrie and Jordan Rudess.
Dream Theater has become a successful progressive rock band, despite the drop in popularity of the genre since the mid-1970s. Although the band has had a few successful hits (notably "Pull Me Under" in the early 1990s, which received extensive MTV rotation), they have mostly stayed underground for their career, feeding off support from their fans.
The band is well known for the technical proficiency of its instrumentalists, who have won many awards from music instruction magazines. Dream Theater's members have collaborated with many other notable musicians. Guitarist John Petrucci has been named as the third player on the G3 tour six times, more than any other invited guitarist, following in the footsteps of Eric Johnson, Robert Fripp, and Yngwie Malmsteen.
The band's two highest selling albums are the gold selling Images and Words (1992), although it reached only #61 on the Billboard 200 charts, and Awake (1994) which reached #32 on the Billboard 200. Recently Systematic Chaos entered US Billboard 200 at #19.  Dream Theater has sold over two million albums in the U.S., and over 8 million albums and DVDs worldwide.from : http://en.wikipedia.org/wiki/Dream_Theater