Extended Reality (XR) is an all-encompassing term that includes augmented reality (AR), virtual reality (VR), and mixed reality (MR) technologies.
Augmented Reality (AR) can be described as experiencing the real world with an overlay of computer generated digital information. AR takes your view of the real world and adds information on top of it. Examples of AR headsets include Google Glass and Focals by North.
Virtual Reality (VR) immerses a user in an entirely simulated environment that shuts out the physical world. Using VR devices such as HTC Vive, Oculus Rift or Google Cardboard, users can observe the artificial world, move around in it, and interact with virtual features or items.
Mixed Reality (MR) lets the user see the real world while also seeing believable virtual objects. Virtual objects are anchored to a point in real space and making it possible to interact with the digital objects. Examples of MR headsets are the Hololens and the Magic Leap One.