Poker is a card game in which players place bets on the strength of their hand. The player with the best hand wins the round and all money bet during that round. The game can have many variations, but most of them share these aspects:
Each player is dealt five cards. The player can choose to raise, call, or check (refuse to bet). Players may also bluff by betting that they have a superior hand. This can win them the pot, or it may cause other players to fold. There is typically a main pot and several side pots.
The main pot is won by a player with the best five-card hand. If more than one player has a winning hand, then the highest-ranking hand wins (five aces beats five kings). A flush contains any five consecutive cards of the same suit. A straight contains any five cards of the same rank in sequence but from more than one suit. A pair contains two cards of the same rank, and a third unmatched card.
Some variants of poker require that all players make a mandatory bet (called a blind bet) before being dealt their cards. Other variants allow players to raise or call any amount of money during a betting interval. A player can also choose not to reveal his or her hand (but cannot win the round). If a player raises, they must continue raising by an amount equal to the previous bet until they have raised at least an established minimum.