Blackjack, also known as twenty-one, is a comparing card game between player and a dealer, where player in turn competes against the dealer. It is played with two or more decks of 52 cards. The objective of the game is to beat the dealer in one of the following ways.

1. Get 21 points on the player first two cards called a "blackjack" , without a dealer blackjack.
2. Reach a final score higher than the dealer without exceeding 21, or
3. Let the dealer draw additional cards until their hand exceeds 21.

The dealer is also dealt two cards, normally one up (exposed) and one down (hidden). Face cards (Jack, Queen, and King) are all worth ten. Aces can be worth one or eleven. A hands value is the sum of the card values. Player is allowed to draw additional cards to improve their hands. A hand with an ace valued as 11 is called "soft", meaning that the hand will not bust by taking an additional card, the value of the ace will become one to prevent the hand from exceeding 21. Otherwise, the hand is "hard".

Once the player has completed their hands, it is the dealers turn. The dealer hand will not be completed if all players have either busted or received Blackjacks. The dealer then reveals the hidden card and must hit until the cards total 17 or more points. Player wins by not busting and having a total higher than the dealer, or not busting and having the dealer bust, or getting a blackjack without the dealer getting a blackjack. If the player and dealer have the same total (not counting blackjacks), this is called a "push", and the player typically does not win or lose money on that hand. Otherwise, the dealer wins.