The minimax score is used in the minimax algorithm for two-player zero-sum game. For each move if it is your oppponent's turn you look for the move that minimises your score (maximises theirs), that is the worst-case move your opponent could make. If it is your move you choose the one that maximises your own score. Of course when calculating the board position after a move you can use the same method recursively or a heuristic evaluation if the search depth is too great.
to find minimax score of n
find minimax score of each child of n
if it is first_players turn
score of n is the maximum of the children's scores
if it is opponents_players turn
score of n is the minimum of the children's scores
find minimax score of each child of n
if it is first_players turn
score of n is the maximum of the children's scores
if it is opponents_players turn
score of n is the minimum of the children's scores
Used in Chap. 11: page 152
Used in glossary entries: heuristic evaluation function, minimax search, zero-sum game
Minimax search on a game tree.