Blackjack is a game of chance and skill. The player’s goal is to beat the dealer by having a higher unbusted hand. If the player and dealer have the same point value, this is called a tie (or push) and bets are returned without adjustment. Blackjack rules differ slightly from casino to casino, and there are many variations in the game. Some of these differences are based on house edge, which is the statistical advantage that the casino has over players. However, the casino’s edge is less than 1% over the long run for players using basic strategy.
The rules of blackjack are generally set by casino regulations, but casinos may permit some rule variations at their discretion. Blackjack games are played with six or eight decks of cards. Some casinos offer a side bet called insurance, which pays when the dealer has an ace up. Some casinos also offer other side bets such as doubling down and splitting.
Some players use card counting techniques to improve their odds of winning. This involves keeping track of the concentration of high cards, such as aces and 10s, in the deck. Players who count correctly increase their bets when the deck is favorable to them and decrease their bets when the deck is favorable for the dealer. There are many different card-counting systems; the most complex ones are detailed in blackjack books.
Unlike most other casino games, blackjack allows players to double down and split their hands. This increases the chances of a higher-valued hand being dealt, but it also raises the risk of losing the original bet. Players should never re-split an ace unless the dealer has an ace up and they are not betting on a blackjack.
After all the players who want to buy insurance have placed their bets, the dealer will check her hole card (using a viewing window in the table) for a ten underneath. If she has a ten, the players who paid insurance will win their original bets back. However, if the dealer does not have a ten underneath, she will take all the insurance wagers and continue dealing her hand as normal.
A player total of 21 on the first two cards is known as a “blackjack” or a “natural”, and automatically wins, unless the dealer has one too. Players are paid 3:2 on their blackjack bets if they have a natural, and if the dealer has a blackjack, the player loses his or her bet.
When a player holds a natural against a dealer’s blackjack, the player will often be offered “even money” by the dealer. This is a poor bet for the player, as the player will only win his or her bet back if the dealer busts. If the dealer does not have a blackjack, and the player has a natural, the hand is a push and the bets are returned to the players without adjustment. Insurance is a bad bet for the dealer too, as it pays 2:1 and the true odds of a dealer having a blackjack are very close to 9:4 (2.25:1).