Poker is a card game in which players wager money on the outcome of a hand. The game can be played with two or more people and the object is to win the pot, which is the sum of all bets made in a single deal. The winning hand is determined by a combination of chance and skill, and the most common hands include pairs, three of a kind, four of a kind, straights, and flushes. In some forms of poker, bluffing is allowed.

A player may bet (match or raise) any time it is their turn to act, but they can also check (decline to make a bet while reserving the right to call later in the round). If all players check on a betting street, the dealer will reveal the final fifth community card, known as the river, and the showdown begins.

During a showdown, each player will reveal their hole cards and the player with the best hand wins the pot. The dealer will then shuffle the remaining cards and deal them out to the players one at a time, starting with the player on the left.

While there is a significant element of luck in poker, the long term expectations of successful players are determined by a combination of knowledge, psychology, and game theory. A good understanding of these principles is a prerequisite to being able to successfully bluff other players and improve your chances of winning.