Poker is a card game played between two or more players, using cards and chips to bet on the outcome of the hand. It has become an international phenomenon, enjoyed in virtually every country where card games are played. There are many different variations of poker, but most have the same essential features. The highest-ranking hands are a royal flush (four matching cards of the same rank) and a straight (five consecutive cards of the same suit). A pair is also acceptable. In some variations the joker, known as the bug, counts as a fifth ace but otherwise has no special value. The number of players varies, but for best results six to eight are ideal.

The object of the game is to win the pot, which is the sum total of bets made by all players in any one deal. A player may win the pot by having the highest-ranking hand or by making a bet that no other players call. The game is usually played with an ante and blind bet, but in some cases the first player to act may choose not to make either of these bets.

Unlike most card games, the majority of Poker bets are not forced. Rather, players place money into the pot voluntarily, choosing to do so for various reasons, ranging from believing that their bet has a positive expected value to attempting to bluff other players. In the long run, the decisions made by players based on probability theory and psychology often have a substantial effect on the outcome of any particular hand.

In a typical poker game, the dealer is responsible for shuffling and dealing the cards. He offers the shuffled pack to the player on his left for a cut, and then deals the cards one at a time, face up or down, according to the rules of the specific game being played. The turn to bet passes from player to player, with each player having the option of raising or dropping.

Once the betting interval has reached its end – this may be after only one round or over several, depending on the variant being played – the players show their hands and the highest-ranking hand takes the pot. In the event of a tie among the players with the highest-ranking hands, the pot is split evenly.