Whereas VR goggles immerse a user in a computer-generated environment, AR uses semi-transparent goggles, which overlay computer-generated graphics onto a user's view of the physical world.
The MREAL System for Mixed Reality (that's the full name -- or, if you want to drill down even further: the headset is the HM-A1 and the software platform is MP-100) generates video of one's surroundings using a pair of cameras positioned in front of the wearer's eyes, which is combined with computer-generated graphics.
Marilyn and Bogie are computer-generated likenesses created by Nadia and Daniel Thalmann, computergraphics professors working at the University of Geneva and the Swiss Federal Institute of Technology, respectively.