Poker is a card game involving betting between a small group of players. It involves a combination of probability, psychology and game theory. Although it relies heavily on chance to win, the decisions made by the players are based on their own assessment of expected value and their attempt to bluff other players for various strategic reasons.

Poker requires a lot of concentration. A good poker player pays attention not only to the cards but also to their opponents, observing their actions and body language. This helps them collect all the information they need to make a sound decision. The game also teaches them to be more disciplined and patient, which is a useful skill in their private lives.

A poker hand contains five cards of the same rank and suit. A flush is a series of consecutive cards of the same suits, while a straight is a sequence of five consecutive cards that skip around in rank but are all from the same suit. Three of a kind is three cards of the same rank, and two pairs are two cards of the same rank with one unmatched card.

A player can choose to bet or check. If they want to increase their bet, they need to say “raise” before the action is on them. A raise can be anywhere from half the previous amount to double it. If they check, they pass their turn to act and wait for other players to call or fold.