Greek stratēgia generalship, from stratēgos
- Date: 1810
- 1 a (1) : the science and art of employing the political, economic, psychological, and military forces of a nation or group of nations to afford the maximum support to adopted policies in peace or war (2) : the science and art of military command exercised to meet the enemy in combat under advantageous conditions
- b : a variety of or instance of the use of strategy
- 2 a : a careful plan or method : a clever stratagem
- b : the art of devising or employing plans or stratagems toward a goal
- 3 : an adaptation or complex of adaptations (as of behavior, metabolism, or structure) that serves or appears to serve an important function in achieving evolutionary success <foraging strategies of insects>
In military usage, strategy is distinct from tactics, which are concerned with the conduct of an engagement, while strategy is concerned with how different engagements are linked. How a battle is fought is a matter of tactics: the terms and conditions that it is fought on and whether it should be fought at all is a matter of strategy, which is part of the four levels of warfare: political goals or grand strategy, strategy, operations, and tactics.
Strategies in game theory
In game theory, a strategy refers to one of the options that a player can choose. That is, every player in a non-cooperative game has a set of possible strategies, and must choose one of the choices.
A strategy must specify what action will happen in each contingent state of the game - e.g. if the opponent does A, then take action B, whereas if the opponent does C, take action D.
Strategies in game theory may be random (mixed) or deterministic (pure). That is, in some games, players choose mixed strategies. Pure strategies can be thought of as a special case of mixed strategies, in which only probabilities 0 or 1 are assigned to actions.