Virtual reality refers to a simulated experience that can be same or different as compared to the actual world. It uses multi-projected environments that generate realistic sounds, images and other sensations that simulate a person's physical presence in the virtual world. A user can move and look around the virtual world with the help of virtual reality equipments. Virtual reality headsets and head-mounted displays are the tools used to generate this artificial world. There are various methods used by this discipline to create the artificial world. Some of these are avatar image-based virtual reality, desktop-based virtual reality and simulation-based virtual reality. This field finds its applications in areas such as entertainment, psychology and social sciences, and medicine. This book provides comprehensive insights into the field of virtual reality. It is a valuable compilation of topics, ranging from the basic to the most complex theories and principles related to this discipline. As this field is emerging at a rapid pace, the contents of this book will help the readers understand the modern concepts and applications of the subject.