Virtual reality (or VR) is a system that allows individuals to interact with a computer-simulated environment. There is much debate about the origin of the term, although it seems to have come into popular usage in the 1970s. Ivan Sutherland [b. 1938), an American engineer, was one of the first to explore the potential of computers to enable people to have experiences that are unavailable to them in real life.
In 1960 cinematographer Morgan Heilig built a single-user console called the Sensorama, which stimulated all the senses of the user in an all- surrounded environment. Heilig's concept involved only passive viewing, but many of his initial ideas were used by Harvard postgraduate student Sutherland. Sutherland wanted to develop a head-mounted display that enabled the wearer to look into a virtual world that would appear completely real. The user could fully interact with this virtual world, which would be maintained by a computer.
In 1968, aided by his student Bob Sproull, Sutherland built a primitive head-mounted display system that was tethered to a computer. The initial invention was so heavy that it had to be suspended from the ceiling, and so intimidating that Others nicknamed it the Sword of Damocles. The system displayed images that were relayed from the computer, presenting the images in stereo, which gave the illusion of three dimensions. It also tracked the user's head movements so that the field of view could be constantly updated.
Sutherland's invention has seen applications in flight simulators and movies such as The Matrix.
