Poker is a card game in which players bet based on their hands. It is played in casinos, private homes and on the Internet.
The rules vary widely from game to game, but all games involve one or more rounds of betting and a showdown between the best hand and the player with the lowest. The game is most popular in North America, where it originated and where it still thrives, albeit with a different set of rules to those in other parts of the world.
In Poker, a hand is ranked according to its odds (probability). Two or more identical hands tie and divide any winning equally. Ties are broken by the highest card, which can be either a pair or a higher-ranking card, such as a five or a king.
A five-card hand beats a straight flush, while a four-card hand wins against a three-card hand. In some poker variants the ace is treated as the lowest card, and this makes 7-5-4-3-2 a low hand in stud and 6-4-3-2-A a low hand in draw.
During each betting interval, each player must place the number of chips (representing money) that is designated by the specific variant of poker being played. This is called the ante, and may also be an amount for blinds or bring-ins.
In many poker variants, the antes and blinds are fixed amounts, while the raise is an amount that changes depending on the stakes of the game. In tournaments, the buy-in is usually fixed.