Strategy

Strategy (Greek "στρατηγία"—stratēgia, "art of troop leader; office of general, command, generalship" ) is a high level plan to achieve one or more goals under conditions of uncertainty.

Strategy is important because the resources available to achieve these goals are usually limited.

Strategy is also about attaining and maintaining a position of advantage over adversaries through the successive exploitation of known or emergent possibilities rather than committing to any specific fixed plan designed at the outset.

Henry Mintzberg from McGill University defined strategy as "a pattern in a stream of decisions" to contrast with a view of strategy as planning while Max McKeown (2011) argues that "strategy is about shaping the future" and is the human attempt to get to "desirable ends with available means".

Military theory
In military theory, strategy is "the utilization during both peace and war, of all of the nation's forces, through large scale, long-range planning and development, to ensure security and victory" (Random House Dictionary).

Strategies in game theory
In game theory, a strategy refers to the rules that a player uses to choose between the available actionable options. Every player in a non-trivial game has a set of possible strategies to use when choosing what moves to make.

A strategy may recursively look ahead and consider what actions can happen in each contingent state of the game—e.g. if the player takes action 1, then that presents the opponent with a certain situation, which might be good or bad, whereas if the player takes action 2 then the opponents will be presented with a different situation, and in each case the choices they make will determine our own future situation.

Strategies in game theory may be random (mixed) or deterministic (pure). Pure strategies can be thought of as a special case of mixed strategies, in which only probabilities 0 or 1 are assigned to actions.

Strategy based games generally require a player to think through a sequence of solutions to determine the best way to defeat the opponent.