Alpha-Beta
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
Alpha-beta pruning speeds minimax by tracking the best guarantee found so far and abandoning any branch already certain to fall short of it.
Show
Once one option guarantees 4, any branch whose ceiling drops to 2 can be closed unread — its remaining leaves cannot matter.
Watch for
Pruning changes which leaves get read, never which move gets chosen.