Poker is a card game in which players place bets on the relative strength of their hands. The higher the rank of a poker hand, the more it is worth. The game also allows players to bluff, betting that they have the best hand while hoping that opponents will call their bet. This form of bluffing is often considered the essence of poker strategy.

There are a large number of possible variants of the game, but all share certain fundamental features. For example, the game almost always takes place using chips that represent money. The standard denominations are white chips (worth one unit), red chips (worth five whites) and blue chips (worth 10 whites). In a game with seven or more players, each player must buy in for at least 200 chips.

After each betting interval, the players who remain show their cards and compete for an amount of money or chips contributed by all the players in that deal. This amount is known as the pot. The highest-ranking poker hand wins the pot. If there are identical hands, they tie and share any winnings equally.

Tournaments are competitions that involve a set number of matches played by a fixed group of competitors, with the winner determined by the total number of points scored. These are common in sports and games where the number of competitors in a single match is limited, such as team sports, racket sports, combat sports and some board games.