2.2. Virtual Reality in Education

There are different types of virtual worlds ranging from a simple virtual environment with text, no audio, and one observer, to environments which are more complex containing sophisticated computer graphics, audio, and interaction with objects and humans. This variety of virtual worlds represents the difference between ``presence'', ``immersion'', and ``interactivity''. Presence is the (mental) feeling of being in a virtual space, such as MOOs, virtual walk through's, or even books and films. Immersion is the complete visual and auditory submersion into the virtual world through VR systems such as the helmet-mounted display (HMD) or the CAVE(tm). Interactivity refers to how reactive the system is in response to the user's actions or how much power the user has to modify the environment.

Based on the above, the virtual reality environments which are designed specifically for education typically fall into three categories. The first includes networked text-based virtual environments, which are highly interactive but not immersive. The second involves desktop virtual reality simulations, where interactivity is usually limited but varies according to the control given by the program, and immersion also varies but is not easily provided. The third category includes the immersive VR environments, where immersion is high, but interactivity may be limited, depending on the complexity of the virtual world. The following sections will present an overview of the current state of educational VR projects which fall into these categories.


2.2.1. Networked Text-based Virtual Worlds


2.2.2. Desktop Virtual Reality


2.2.3. Immersive VR projects


2.2.4. The Value of Virtual Reality for Education