Poker is a card game where players combine their own hole cards with the community cards to make a poker hand. The game can be played with a single hole card, two hole cards, or no hole cards at all (play the board). Depending on the variant, there is one or more rounds of betting and the player with the best poker hand wins the pot. The game has many different rules that can vary widely from casino to casino.

The game was first popularized in the United States by television, and it exploded in popularity during the turn of the millennium. It is now an extremely common and very profitable game, both in live and online casinos. There are several types of poker, and each type has specific rules that must be adhered to in order for the game to be fair to all players.

While it is harder to break poker rules in live poker than in online games, mistakes are still sometimes made. A dealer is under immense stress and can be prone to making errors when dealing multiple hands quickly. If a player notices that the dealer has not adhered to poker rules, it is their responsibility to speak up and alert the floorperson. The floorperson will come over to make a final judgment on whether or not the dealer has followed the poker rules.

Other card games that may be referred to as poker include Red Dog and Acey-Deucey, which are similar to blackjack in layout and betting; these games differ from poker by having only one round of betting. Video poker is also based on a basic form of poker and uses the same principles as the other card games.