You`re in the enemy territory, holding your sniper rifle, scanning the horizon for hostile activity. From

the darkness, a new shadow emerges, stealthily moving towards your position. You raise the rifle, aim

for the intruder and squeeze the trigger. The recoil of the gun, the crack of the shot and the sudden

plummet of the shadow tells you that you have found your mark.

You`ve entered the main living room. You go through the arched mezzanine and peek into the master

bedroom. But something`s not right. The door frame ought to be at least half a foot higher. You make a

mental note to talk to your architect and proceed to walk through the rest of the house.

Fairly straightforward scenarios, both of these. In one, you`re a vigilant soldier on patrol duty. In the

other, you`re inspecting your new house. The strange thing in both these scenarios is that neither one

actually exists. There is no gun, nor is there a house. You are just seeing thinking there is, when in fact,

the whole scenario is just made up on demand. This, in a nutshell, is the world of virtual reality.

Virtual Reality, or VR, as it is commonly known, is the one of the most modern advancements in the

world of computer simulations and environments. It is basically defined as a computer generated

realistic creation of a world which exists only in imagination. A person experiencing this world is able to

sense, feel and interact with this imaginary world as if he were traversing a real environment. The overall

experience the user gains is the ability to navigate through, and perform functions with this artificial

scenario with the luxury of not needing to have the real environment. In this article, we take a look at

the development and practical uses of visual reality technology.

In the early 1960s, the US Air Force was looking for ways of training pilots in the art of flying while trying

to negate the risk of training accidents or mishaps. They hit upon a way to accomplish this end. Mockups

of cockpits were constructed with computer screens and speakers inside to provide realistic flying

situations for the trainee pilots to handle. Later in the 1970s, the Massachusetts Institute of Technology

(MIT) created a computer program which could simulate an entire city, including realistic effects such

as street traffic and birds flying overhead. This was the time when the term Virtual Reality came into

prominence.

A virtual reality system works primarily on the concept of user immersion and interaction. Immersion

is the feeling of being an actual part of a world. When the user negotiates and takes meaningful actions

in this world, it is referred to as interaction. The sense of both immersion and interaction is known as

telepresence. For this purpose, the user usually has various devices such as a headset or a wired glove

for input purposes. Head-mounted displays are common in these scenarios as they can easily construct a

fully 3D environment. An immersive experience suffers if a user becomes aware of the real world around

him. Truly immersive experiences make the user forget his real surroundings, effectively causing the

computer to become a non entity. These limitations are fast becoming no more as graphical software

and better data processing hardware gets developed at a rapid pace. The critical part about VR is that

the user should be able to affect the virtual environment, thereby modifying the program, as he sees

fit. Only then does a truly interactive experience occur. This is done by sensors directly linked to the

user`s senses, which in turn detects changes done to the program in the virtual world, and consequently,

generates an appropriate response to that action, in effect, changing the graphics or dimensions of that

environment. Early VR systems relied mainly on the basic senses of hearing and seeing to reproduce

an element of authenticity in the artificially created world. But as technology gets more advanced,

researchers and scientists have included the sense of touch as an input method. Systems that give a user

force feedback and touch interaction are called haptic systems. This technology has enormous obvious

advantages insofar as the user can now truly interact with the program, paving the way for development

of numerous practical applications.

Virtual Reality is now a popular tool among the world`s military training facilities, its reasons being

pretty clear. Trainers and trainees are now able to design experience real-time tactical and strategic

maneuvers and hone critical field skills without the risk of being in a real hostile environment.

Architectural engineers have used VR to simulate building specifications and practicability. The video

gaming community has been using this technology to a large extent in improving gaming experiences by

providing more realistic 3D effects. The medical arena has profited immensely from VR technology, using

it to simulate training sessions for surgeries and other medical procedures.

Virtual Reality systems have not become an everyday application today, but considering the immense

potential of this growing technology and the expansion of electronic networking of the world today, the

day may not be far off where a large part of our industries may be using it to a very large extent.