 Philosophical logic and mathematical logic are not the only illuminating perspectives on games. A third relevant viewpoint is that of computational logic. In modern computation, the paradigm is no longer single Turing machines but interacting systems of multiple processors. These processors may cooperate, but they might also compete for resources. In general, hence, it is useful to study multiple agents engaging in computation, be it within human, artificial or mixed societies. Though doing so, games become a natural model for computation, too. In fact, games are rich multi-agent systems where agents process information, communicate, and engage in actions, all driven by their respective preferences and goals. In the converse direction, computer science themes such as complexity and algorithmics have entered game theory, resulting in the area of  computational game theory (Nisan et al. 2007). For a richer survey of computational logics of agency and games, see van der Hoek and Pauly (2007) and Shoham and Leyton-Brown (2008). The present entry contains occasional links to computation. These are especially prominent for reasoning about temporally extended games and their strategies (Sections  4.2,  4.4) and in the context of gamification  (Section 6),  where games are explored as a novel semantics for classical logical systems.