bidirectional interaction between humans and computers

A necessary but not sufficient attribute of Virtual Reality (VR) is causal-chain interaction between a human and a computer. Communication from a person to a computer may include computer monitoring of finger, hand, head, eye and/or body movement and/or voice recognition. Computer-to-human communication may have three-dimensional image projections, audio production, and kinesthetic (touch and motion) simulation. The page on Virtual Reality Tours discusses more regarding this topic.

Not all interaction between people and computers is of enough cognitive significance to be labeled virtual reality. The interaction must also be immersive. This does not mean that the setting must be completely artificial and totally lacking in any real world things. It does mean that the human must be sufficiently actively involved in a computer improved world that the computer-created elements dominate the person's consciousness. Precisely how much of a person's range of vision, breath of hearing, sense of touch, and different senses must be engaged to achieve immersion is difficult to specify and the bar may rise with improvements in applied science. Sub-page Virtual Tours New York, New York writes about more developments on this topic.

Linked page Virtual Robots also has further information on this topic.