Virtual Reality (VR) is a creation of virtual 3D world in which one can feel and sense the world as if it is real. It is allowing engineers to design machines and Educationists to design AV [audiovisual] equipment in real time but in 3-dimensional hologram as if the actual material is being made and worked upon. VR allows a least-cost (energy wise) and non-invasive mechanism to achieve all our objectives. VR sometimes can be even more powerful than the real world since it allows almost anybody to feel and sense the otherwise forbidden world. In the most popular applications of VR technology, any student viewer simply tours various historical and geographic sites in a three dimensional space; even virtual surgery is also possible. Even in our history VR class, we will be able to visit different historical events. Simulation Based Learning (SBL) is an approach which enables learners to view, touch, hear, and interact with life-like objects in real time. The different types of VR devices are; Head mounted Displays, Data Gloves, VR Simulators, and VR Therapy, Hap tics (Convulsive), Head Trackers, Motion Trackers (MT), 3D Controllers, Stereoscopic Displays, VR Domes, 3D DVD, VR wear, Video Eyeware and VR Software/Kits. Virtual reality can be classified into five modelling types viz., (i) simulation-based; (ii) avatar image-based; (iii) projector-based; (iv) desktop-based; and (v) true immersive based VR. This paper also discusses the six factors for designing educational VR software. The disadvantages of VR are (i) the cost of multiple image-generation systems, (ii) space requirements for rear projection, and (iii) reduced contrast and color saturation due to light scattering.