Define alpha-beta pruning in artificial intelligence?

Alpha-beta pruning is an optimization technique for the minimax algorithm used in decision-making and game theory, particularly in AI for games. It reduces the number of nodes evaluated in the search tree by eliminating branches that cannot possibly influence the final decision. This is achieved by maintaining two values, alpha and beta, which represent the minimum score that the maximizing player is assured of and the maximum score that the minimizing player is assured of, respectively. By pruning these branches, alpha-beta pruning enhances efficiency without affecting the outcome of the minimax search.