Poker is a card game in which players bet on their hands. Each player must put an initial contribution, called an ante or blinds (amount varies by game) into the pot before being dealt cards. These are forced bets that help make the game more interesting and prevent people from folding every hand.
Once the ante has been placed, the dealer shuffles the cards and deals each player five cards. The player can then choose to discard one or more of his cards and draw new ones. The highest ranked hand wins the pot.
During a betting round, players can place additional chips into the pot in order to increase their bet. The other players can then call this bet or fold, meaning they do not want to play their hand. The players that do not fold are considered to be active in the pot and are able to continue to increase their bets until all of them have folded.
The highest ranked hand wins the pot, but players can also win a side pot by bluffing and pretending that their hand is high when it is not. The winner of the side pots is determined by a high card. If there is no high card, then the value of the second highest card is used to break ties. The dealer changes positions each hand, and is known as the button. This button is moved clockwise around the table after each hand.