Poker is a card game that can be played by two or more players and involves betting in chips (representing money, for which poker is almost always played). The goal of the game is to win the pot, which is the aggregate amount of all bets made during one deal. There are many variants of the game, but they all share certain basic principles.

A good poker player can make a lot of money by learning to read his or her opponents. This requires discipline and a sharp focus during games, and also means finding the best game types and limits for their bankrolls. It’s important to learn from the mistakes of other players, too, by observing them and then reflecting on how they might have done differently in the same situation.

A player’s tells are unconscious habits that reveal information about his or her hand to other players. These can include eye contact, facial expressions, and body language. For example, a player may make a gesture or change in posture that indicates he or she has a good hand. A good poker player can often identify the hands that his or her opponents have by observing these tells. This helps him or her decide when to call a bet and when to fold. It also allows him or her to estimate the odds of his or her hand winning. This is called the risk vs. reward calculation.