Game Theory is a branch of mathematics that is used to capture behavior in strategic situations, such as competition and cooperation; conflict and interdependence, when an individual's success in making choices depends on the choices of others. This theory applies rules of strategic games like chess.
Additional meaning of Game Theory:
Described in the book 'Theory of Games and Economic Behavior.' by Oskar Morgenstern and John von Neumann, game theory is associated with decision-theory, and is used to analyze business situations where management-psychology plays an important part.