Dream Theater is an American progressive metal band formed in 1985 under the name Majesty by John Petrucci, John Myung and Mike Portnoy while they attended Berklee College of Music in Boston, Massachusetts. They subsequently dropped out of their studies to concentrate further on the band that would ultimately become Dream Theater. Though a number of lineup changes followed, the three original members remained together until September 8, 2010, when Portnoy left the band. Mike Mangini was announced as the new permanent drummer on April 29, 2011. The band's highest-selling album is the gold-selling Images and Words (1992), w