Virtual reality
Around the same time, Douglas Engelbart used computer screens both as input and output devices. In 1968, Ivan Sutherland, with the help of many students including Bob Sproull, created what was widely considered to be the first head-mounted display (HMD) system for use in immersive simulation applications. It was primitive both in terms of user interface and realism, and the HMD to be worn by the user was so heavy that it had to be suspended from the ceiling. The graphics comprising the virtual environment were simple wire-frame model rooms. The formidable appearance of the device inspired its name, The Sword of Damocles.
Sensorama
Howard Rheingold (in his 1991 book "Virtual Reality") spoke of his trial of the Sensorama using a short film piece that detailed a bicycle ride through Brooklyn, created in the 1950s, and still seemed quite impressed by what it could do more than 40 years later. The Sensorama was able to display stereoscopic 3-D images in a wide-angle view, provide body tilting, supply stereo sound, and also had tracks for wind and aromas to be triggered during the film. Heilig was unable to obtain financial backing for his visions and patents, and so the Sensorama work was halted.