The past is expressed as a structural constraint on the present. Second, however, time must be expressed for each individual allowing for behavioral options including choice behavior. For each individual there is past time and future time. At this level choice behavior can be viewed as maximizing expected utility. By placing the choice in a game context a structured future can be described with uncertain outcomes.
Strategy then becomes the device that links past time and future time.
Strategies are devised from past experience and they define future choices. At the simplest level strategy can be defined in terms of game theory, with rules, payoffs such as zero sums, and other well established features.