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.
VPL Research
VPL Research was one of the first companies that developed and sold virtual reality products. It was founded by VR pioneer Jaron Lanier in 1984. VPL started in the corner of Lanier's cottage in the San Francisco Bay Area. "VPL" stood for "Virtual Programming Languages", and Lanier said that the goal of the company was to bring virtual reality to a mass audience. In 1990, VPL Research filed for bankruptcy and in 1999 all of its patents were bought by Sun Microsystems.