Alternate Reality Games and Augmented Reality Games both fall under the acronym of ARG, but are actually quite different.
Extra Credit now examines the Augmented Reality Game genre. This genre appears to be the furthest out of reach given the technological requirements and costs needed to create seamless experiences. Should someone get their head around those limitations—and I guess wearable technology becomes a thing—it has great potential to blur the line between gaming and the real world.
Source: Extra Credits on Blip