Some Reminiscences on the History of Hardware and Software for Simulation 1963-2003

During the past fifty years the world has changed and simulation has advanced out of all recognition. The author has progressed from very large analogue computers in the early 1960s, through hybrid analogue/digital systems in the late 60s, to design and construction of digital signal processing computers in the 70s, onto early microcomputers in the 80s, used for simulation, and more recently to distributed simulation in the 90s and 00s, always up with the leading edge. This paper summarises some of these developments and considers the current situation and future prospects.