Augmented reality (AR), Mixed reality (MR), Augmented virtuality (AV)

http://en.wikipedia.org/wiki/Augmented_reality
Augmented reality (AR) is a term for a live direct or indirect view of a physical real-world environment whose elements are merged with (or augmented by) virtual computer-generated imagery - creating a mixed reality.

http://en.wikipedia.org/wiki/Mixed_reality
Mixed reality (MR) (encompassing both augmented reality and augmented virtuality) refers to the merging of real and virtual worlds to produce new environments and visualisations where physical and digital objects co-exist and interact in real time. A mix of reality, augmented reality, augmented virtuality and virtual reality.

http://en.wikipedia.org/wiki/Augmented_virtuality
Augmented virtuality (AV) (also referred to as Mixed reality) refers to the merging of real world objects into virtual worlds.