Virtual reality (VR) is an artificial environment that is created with computer hardware and software and presented to the user in a way that makes them feel like they are experiencing a real environment. There are different types of VR systems, including window-on-world systems which use monitors, immersive VR with head mounted displays, telepresence which links sensors to human operators, and mixed reality systems. Important factors in VR systems include visual realism, image resolution, frame rate, and latency. VR has applications in areas like education, medicine, entertainment, and more and its future uses are still developing as customized applications are created.