Blackjack is a casino banking game. It is the most popular of all the card games and is played with a standard 52-card deck. It is part of the Twenty-One family of games, which also includes Pontoon, Vingt-et-Un, and Pontoon-Plus. It originated in France in the seventeenth century and has been adapted into a variety of casino settings. Its rules are similar to poker.

The rules of Blackjack are simple. In addition to being played with two decks, players may double down to a total of two, three, four, or five. If the dealer has a blackjack, you’ll win your bet by two to one, and you’ll have an additional card face up. If the dealer doesn’t have a blackjack, you’ll have to stand. This option is only available for players with a two-card starting hand. Some casinos also limit the amount that can be doubled to five.

Once you’ve decided to double down, you’ll need to decide what amount to bet. The correct amount will depend on the value of your cards. If you double down too much, you’ll lose the opportunity to draw more than one card. The correct play is to double down for the entire amount. In the case of a tie, you’ll want to consult the Blackjack Basic Strategy Engine to determine the correct amount to double down.