Alternate Reality Games and Augmented Reality Games both fall under the acronym of ARG, but are actually quite different. Extra Credit takes a quick look at the Alternate Reality Game half of that genre of games—and yes you can argue that they are games. Perhaps it is because they are unfamiliar to the public and save for a few great examples like Microsoft/Bungie's I Love Bees or Electronic Arts' Majestic, they have been largely untouched by many in the games industry.
Creators of ARGs usually claim that they are not games, denying their existence until the very end, if ever. That's why they are usually no more than elaborate advertising campaigns or activist movements. But they do show great promise beyond that. Alternate Reality Games can get multiple people interacting with and often times advancing the game for others through their own actions. They provide a level of interaction and addictiveness that traditional games don't possess and they do so while claiming to not be game at all. They may not replace the traditional genres like the role-playing game or first-person shooter, but with the prevalence of electronic devices and the Internet in our daily lives, it won't be long before more crop up showing never before seen creativity and ingenuity.
Source: Extra Credits on Blip