About minimax

This algorithm is useful for choosing the best possible worst-case scenario, ie, if your opponent plays perfectly.

The game must be two-player, turn-based and have complete information, meaning that at any given state of the game, both players can see all endgames.

The alpha-beta optimization is an optional speedup to the minimax algorithm that skips subtrees that will not be chosen.

A sub-tree that will not be chosen is a simple scenario: if your opponent wants to minimize your gains, they will simply pick the subtree with the lowest expected score during their turn.

Therefore, we know that exploring that sub-tree any further is futile, it won’t be chosen.