Blackjack strategy involves making decisions based on the player's hand and the dealer's visible card. Basic strategies include when to hit, stand, double down, or split pairs. Players often refer to a strategy chart that outlines the best moves based on their hand value and the dealer's upcard. Using a basic strategy can reduce the house edge, making it more likely for players to win in the long run. Advanced strategies, like card counting, can further improve a player's chances by keeping track of high and low cards remaining in the deck. However, card counting requires practice and is not foolproof.