Blackjack is a casino card game in which the goal is to beat the dealer by having a hand value closer to 21 than his or hers. Players place wagers based on the cards they receive, and can hit, stand, double down, or split pairs. Number cards are worth their face value; picture cards are worth 10; and Aces can count as either 1 or 11. When a player’s initial two cards total 21, it is called a “blackjack,” and is paid out one and a half times the original bet. If the dealer also has a blackjack, the hand is considered a tie and the bets are returned without adjustment.

To play blackjack, a player must be at least 18 years old and have a valid state or tribal gaming license. In addition, the game requires good attention to detail, a strong memory, and the ability to calculate odds and probability. The game can be found in most casino card rooms, and some offer separate tables for high-limit players.

A player’s bankroll is key to success at blackjack, and effective money management requires a predetermined amount that the player is willing to lose per round. This helps the player avoid making emotional decisions that could result in large losses, and it reduces the risk of financial strain. In general, a player should bet no more than two percent of his or her total bankroll on each hand.

Blackjack has been the subject of extensive study by mathematicians and computer scientists. A famous example is a book published in the 1960s by Edward O. Thorp, which included charts showing an optimal strategy for the game. More recently, a mathematical technique called genetic algorithms has been used to find close-to-optimal strategies for the game.

While there are many different ways to play blackjack, the basic rules are the same. Each player begins the game with two cards, and may choose to stand, hit, or double down based on their hand value and the dealer’s up card. Players may also place a side bet, known as insurance, which pays out when the dealer has an ace up.

When playing blackjack, it is important to keep in mind that the house has an edge over the player, so winning hands are rare. To increase your chances of winning, it is important to understand the odds of each action, as well as the probabilities of hitting a specific combination. A blackjack calculator can help you determine the best bet for each situation. This will allow you to maximize your profits while minimizing losses. If you are a beginner to blackjack, it is important to practice before betting real money. Also, be sure to tip the dealer after each game. This is a great way to show your appreciation for their hard work. Good luck!