Game Theory is the study of strategic interactions, that is, situations in which there is interdependence among the parties to the interaction. Hence, you need to anticipate your opponent's next moves and, accordingly, decide on how to act, while also knowing that s/he is trying to do the same thing. Game Theory is an analytical tool used to explain and predict such interactions, for example between humans, animals, nations, firms, with applications in a wide range of fields such as economics, political science, sociology, business, law, biology, computer science.