What is Augmented Reality?

Have a look at this Wikipedia article.  It does a much better job of explaining AR than we ever could.


What is the difference between Augmented Reality and Virtual Reality?

AR overlays virtual objects on top of a real world view.  VR creates a completely fictitious world.


What is the difference between Augmented Reality and Mixed Reality?

This cuts a relatively fine line.  In the strictest sense, Augmented Reality displays information on top of a real display.  While Mixed Reality also overlays information on top of a real display, it enables you to interact with the virtual content.