Genres.. ?

[sc94597]

Sandbox isn't a genre rather than a way to describe a game as nonlinear. For Example most wrpgs are sandbox games , because they have the following classifications found here http://en.wikipedia.org/wiki/Sandbox_game#Common_features_of_sandbox-style_video_gaming/
* Never-ending gameplay: The user is allowed to play forever, and the game (or mode) is generally designed with this in mind rather than the completion of particular goals or levels in order to reach a grand finale.
* Freedom to experiment: The player can choose his or her own path in the game, either with no consequences or with consequences that can later be undone (often resulting in a flexible and organic development of the player's character or even of the entire game).
* Non-linear or nonexistent plot. If there is a plot at all, the player can simply ignore it, or there is a branching plot that evolves based on user choices (resulting in a game that is never the same twice unless played in exactly the same manner).

I would list GTA as an Action/Adventure with a sandbox style.