Types of VR experiences
Seated VR includes devices such as Google Cardboard, Samsung Gear VR and Oculus Rift. These experiences are based around the user remaining roughly stationary. In some cases there is not positional data available (e.g. Google Cardboard) and only the orientation of the headset is used.
Room Scale VR
Room Scale VR includes devices such as the HTC Vive and the Oculus Rift. Room scale experiences are designed to allow a small or large amount of movement away from the origin position of the scene.
A Magic Window experience benefits from not requiring a VR headset at all. In fact it isn't really VR but a immersive way of displaying content and using the gyroscope and accelerometers of modern smartphones to set your camera position.