This paper provides an introduction to the technology of virtual reality (VR) and its possibilies for education and training. It focuses on immersion as the key added value of VR, and analyzes what cognitive variables are connected to immersion, how it is generated in synthetic environments, what immersion is, and what its benefits are. The central research question is the value of tracked, immersive visual displays over non-immersive simulations. The paper provides a brief overview of existing VR research on training and transfer, education, and procedural, cognitive and maintenance training.