What is game theory?

Context: Game theory is the study of mathematical models of strategic interactions among rational agents. It has applications in all fields of social science, as well as in logic, systems science and computer science. Originally, it addressed two-person zero-sum games, in which each participant's gains or losses are exactly balanced by those of other participants. In the 21st century, game theory applies to a wide range of behavioral relations; it is now an umbrella term for the science of logical decision making in humans, animals, as well as computers.

Answer: Game theory is a scientific study of mathematical models and strategies. It has wide applications in all aspects of social science, system, and computer science that include zero-sum games and behavioral relations. Currently Game Theory is an umbrella term for decision making in humans, animals, and computers.