The simplest form of virtual reality is a 3-D image that can be explored interactively at a personal computer, usually by manipulating keys or the mouse so that the content of the image moves in some direction or zooms in or out. More sophisticated efforts involve such approaches as wrap-around display screens, actual rooms augmented with wearable computers, and hap tics devices that let you feel the display images.
Virtual reality can be divided into:
1) The simulation of a real environment for training and education.
2) The development of an imagined environment for a game or interactive story.
How virtual reality works?
If the last applies to you, you're likely a computer scientist or engineer, many of whom now avoid the words virtual reality even while they work on technologies most of us associate with VR. Today, you're more likely to hear someone use the words virtual environment (VE) to refer to what the public knows as virtual reality. We'll use the terms interchangeably in this article.
Naming discrepancies aside, the concept remains the same - using computer technology to create a simulated, three-dimensional world that a user can manipulate and explore while feeling as if he were in that world. Scientists, theorists and engineers have designed dozens of devices and applications to achieve this goal. Opinions differ on what exactly constitutes a true VR experience, but in general it should include:
Three-dimensional images that appear to be life-sized from the perspective of the user
The ability to track a user's motions, particularly his head and eye movements, and correspondingly adjust the images on the user's display to reflect the change in perspective
In this article, we'll look at the defining characteristics of VR, some of the technology used in VR systems, a few of its applications, some concerns about virtual reality and a brief history of the discipline. In the next section, we'll look at how experts define virtual environments, starting with immersion.