Poker is a card game where players place chips (representing money) into a pot for wagers on the outcome of a hand. Each player chooses to bet based on the expectation of winning, which is influenced by a combination of probability, psychology and game theory. With the exception of initial forced bets, money is placed into the pot voluntarily by players who believe the bet has positive expected value. This allows players to balance risk and reward over the long run.

Each betting interval consists of one or more rounds of betting, according to the rules of the particular poker variant being played. The first player to act places a chip into the pot and can then either call the bet or raise it. In either case he must match or exceed the amount of the last bet in order to stay in the pot. Players who continue to play after the player to their right has raised their bet are known as active players.

Once the initial betting round is complete the dealer puts three cards face-up on the board that everyone can use (the flop). Players still in the hand can then bet again. In general, it is best to raise a strong hand instead of limping – if you think your hand is solid you should try to price all the worse hands out of the pot.

If you have pocket kings and an ace shows up on the flop it should be very easy to fold, no matter what else is in the deck. This prevents you from trying to hit a draw that may not pay off and saves you money in the long run.