Poker

 

Poker is a family of card games in which players wager on which hand is the best according to the rules of the game in ways that are comparable to these rankings. Poker games differ in deck construction, number of cards in play, number dealt face up or face down, and number shared by all players, but they all include rules that include one or more rounds of betting.

In the majority of modern poker games, the initial round of betting starts with one or more players placing a forced wager (the blind or ante). In traditional poker, each player bets based on how valuable they perceive their hand is in comparison to the other players. The action then moves clockwise, with each player having to either match (or "call") the previous stake's maximum sum, or fold, forfeiting the amount bet thus far as well as any further involvement in the hand. When a player matches a wager, he or she has the option to "raise" (increase) the wager. When all players have either called or folded the last stake, the betting round is over. On any round in which all but one player folds, the surviving player takes the pot without having to expose their hand. If more than one player is still in the game after the last betting round, a showdown is held in which the hands are disclosed and the player with the best hand wins the pot.

With the exception of early forced bets, money is only freely put into the pot by a player who believes the bet has a positive expected value or is attempting to bluff other players for various strategic reasons. While the outcome of any given hand is influenced by chance, the players' long-term expectations are dictated by their behaviors, which are based on probability, psychology, and game theory.

Since the turn of the century, poker has grown in popularity, evolving from a primarily recreational activity enjoyed by a small group of enthusiasts to a widely popular activity enjoyed by both participants and spectators, including online, with many professional players and multimillion-dollar tournament prizes.