Poker is a card game in which players wager against each other for an amount of money or chips contributed by all the participants, called the pot. It is a game of chance, but it also involves a large degree of skill and psychology.

The game is played with a standard 52-card pack, sometimes with one or two jokers added (depending on the variant). Occasionally, when speeding up the deal, a second deck of cards is used. This is shuffled as the first is dealt and passed to the next dealer. A missing joker is treated as a scrap of paper and does not affect the outcome of a hand.

Before the cards are dealt, all players must ante a pre-determined amount into the pot (if there is no ante). Players receive two cards face down, which they keep secret and are referred to as their hole cards. Then players bet into the pot based on their predictions of what the other players are holding and how they will behave.

The game has a number of variants, most notably Texas hold ‘em, which replaced seven-card stud as the leading form of poker in casinos and on television. The game has many rules, some of which vary by region. The prevailing rules are managed by the Professional Tournament Directors Association (Poker TDA), an organization that brings together the managers of major live and online poker rooms, circuits, leagues and independent poker events.