Final answer:
The main technology used in an exocentric virtual reality environment is computer graphics, which create the perspective of an outside observer within the immersive simulation.
Step-by-step explanation:
Within the context of virtual reality technology, the main technology used in an exocentric environment is computer graphics. Exocentric environments are those in which the user views the action from a perspective outside of the environment being simulated. This contrasts with egocentric environments, where users experience the perspective from within the virtual world. Virtual reality relies on advanced computer graphics to create immersive environments that can simulate real-world experiences or create fantastical settings, such as simulating the appearance of weightlessness in movies like Gravity and The Martian. Whether virtual reality will largely supplant physical travel remains to be seen; however, it presents an alternative to experience places and situations without the material costs and resources associated with traditional transportation.