Poker is an international card game played with a standard 52-card deck. It is enjoyed in virtually every country that has card games.

The first player to deal (called the dealer) shuffles and deals the cards, one at a time, faceup. This is followed by a first betting round, which may be several. After each betting round, the players’ hands develop in some way, often by being dealt additional cards or replaced by cards previously dealt.

In the next betting interval, the player to the left of the dealer (the small blind) acts first; he may fold, call the small blind, or raise. If no other player calls, the small blind may check.

Each betting interval ends when the betting turn has returned to the player who made the last bet, or when all players have checked. If a player raises, the round is over and all bets are gathered into the central pot.

Variants of the game are common and vary widely in rules, but all variants share the same basic strategy. The player who holds the best hand wins the pot.

Most variants of poker allow a player to bet or raise only if he has a hand that he expects to beat. The outcome of a hand depends on a combination of probability, psychology, and game theory.

The most common winning hand in poker is a straight, which consists of five cards in sequence. Other valid hands include two pairs, three of a kind, and fours or better.