Poker is a card game for two or more players where the objective is to form the highest-value hand. The game can be played with any number of cards and a pot may be won either by having the best hand or by raising all other players’ bets to a level at which they cannot reasonably call (i.e. a “showdown”). The game relies on the application of probability, psychology and game theory. It is a game that requires great concentration and discipline.

The rules of poker vary by game, but the majority of games are played with a fixed number of cards and a fixed number of betting rounds. During each betting round, a player must place chips into the pot equal to or greater than the amount placed by the player before him. A player who raises a bet during one of these rounds is called an active player.

It is important to understand the basic rules of poker, including the order of different hands. The highest-ranking hand is a Royal flush (Jack-Queen-King-Ace of the same suit). Other high-ranking hands include Straight, Flush, Four of a kind, Full house and Two pair.

It is also important to learn how to read other players and look for their tells. These can be subtle, but can often indicate whether or not they are holding a good hand. A player who calls all night and then suddenly makes a big raise is probably holding a strong hand. Beginners should focus on learning to recognize the tells of their opponents, which may include things like their eye movements, idiosyncrasies, hand gestures and betting behavior.