 In one concrete perspective, a strategy is akin to a program that instructs the agent on how to navigate a game tree. Hence, a natural logic of strategies uses the language of  propositional dynamic logic of programs  PDL, an approach that will return later. As programs are in general non-deterministic, such logics let a strategy recommend one or more actions the agent should take at each turn. In this perspective, strategies resemble plans that might remain partial.