Strategos

Strategos, plural strategoi, (Greek: στρατηγός, pl. στρατηγοί; Doric Greek: στραταγός, stratagos; literally meaning "army leader") is used in Greek to mean military general. In the Hellenistic world and the Byzantine Empire the term was also used to describe a military governor. In the modern Hellenic Army it is the highest officer rank.

Classical Greece

In its most famous attestation, in Classical Athens, the office of strategos existed already in the 6th century BC, but it was only with the reforms of Cleisthenes in 501 BC that it assumed its "classical" form: a board of ten strategoi who were elected annually, one from each tribe (phyle). The ten were of equal status, and replaced the polemarchos, who had hitherto been the senior military commander. At Marathon in 490 BC (according to Herodotus) they decided strategy by majority vote, and each held the presidency in daily rotation. At this date the polemarchos had a casting vote, and one view is that he was the commander-in-chief; but from 486 onwards the polemarchos, like the other archontes, was appointed by lot. The annual election of the strategoi was held in the spring, and their term of office coincided with the ordinary Athenian year, from midsummer to midsummer. If a strategos died or was dismissed from office, a by-election might be held to replace him.

Strategy (game theory)

In game theory, player's strategy is any of the options he or she can choose in a setting where the outcome depends not only on his own actions but on the action of others. A player's strategy will determine the action the player will take at any stage of the game.

The strategy concept is sometimes (wrongly) confused with that of a move. A move is an action taken by a player at some point during the play of a game (e.g., in chess, moving white's Bishop a2 to b3). A strategy on the other hand is a complete algorithm for playing the game, telling a player what to do for every possible situation throughout the game.

A strategy profile (sometimes called a strategy combination) is a set of strategies for all players which fully specifies all actions in a game. A strategy profile must include one and only one strategy for every player.

Strategy set

A player's strategy set defines what strategies are available for them to play.

A player has a finite strategy set if they have a number of discrete strategies available to them. For instance, in a single game of rock-paper-scissors, each player has the finite strategy set {rock, paper, scissors}.