Blackjack

Blackjack is a card game where the goal is to beat the dealer by getting closer to 21 than the dealer without going over. It is one of the oldest and most popular casino games in the world, with roots in 18th-century France where it was called Vingt-et-Un — twenty-one.

What sets blackjack apart from most other casino games is that the player's decisions actually affect the outcome. There is a mathematical basic strategy that, if followed consistently, reduces the house edge to between 0.5 and 1 percent — depending on the game's rules. This makes blackjack one of the most favourable games for the player in a casino.

Blackjack is played with one or more standard decks of cards (usually 4–8). Card values are: number cards are worth face value, face cards (J, Q, K) are worth 10, and aces are worth 1 or 11 — whichever is more favourable.

The game begins with all players and the dealer receiving two cards. Players' cards are visible; the dealer has one visible card and one face-down. Players then choose their action:

With correct basic strategy the house edge in blackjack is typically between 0.5 and 1 percent, depending on the game's specific rules. This is among the lowest house edge figures in a casino. By comparison, European roulette has a house edge of 2.7%, and many slot games have 3–5%.

Basic strategy is a set of mathematically optimal decisions for every combination of the player's hand and the dealer's visible card. It is calculated using computing power and is entirely legal to use.

Some fundamental principles: Always stand on 17 or higher. Always double down on 11 against the dealer's 2–10. Always split aces and eights. Never stand on 12–16 against the dealer's 7 or higher — take a card. Basic strategy does not reduce the house edge to zero, but it minimises it mathematically. Playing without basic strategy increases the house edge significantly.