Jaron Lanier coined (or popularized, depending on your sources) the term virtual reality. Jaron Lanier designed and built the first most complete commercially-available virtual reality system. It included the Dataglove and the EyePhone head-mounted display. The Dataglove would evolve into the Nintendo Powerglove. The Dataglove was able to track hand gestures through a unique trait of fiber optic cable. If you scratch a fiber optic cable, and shine light through it while it is straight, very little of the light will escape. But if you bend the scratched fiber optic cable, light will escape, and the more you bend it, the more light escapes. This light was measured and then used to calculate finger movements.