The Cray X-MP was a supercomputer designed, built and sold by Cray Research. It was announced in 1982 as the “cleaned up” successor to the 1975 Cray-1, and was the world’s fastest computer from 1983 to 1985. The principal designer was Steve Chen. The X-MP’s main improvement over the Cray-1 was that it was a shared-memory parallel vector processor, the first such computer from Cray Research. It housed two CPUs in a mainframe that was nearly identical in outside appearance to the Cray-1.