Virtual reality (VR) uses computer-generated graphics and sounds to create an immersive, interactive simulated reality. It emerged in the 1980s and builds on concepts dating back to the 1800s. There are three main types: immersive VR uses headsets to place users in virtual worlds; telepresence allows remote control of devices; and mixed reality combines virtual and real elements. VR has applications in fields like military, education, healthcare, entertainment, and more. Current challenges include cost, accuracy, and simulator sickness, but the technology is improving.