Poker is a card game in which players place bets with chips in a central pot. Each player is dealt two cards and the goal is to make the best five card hand using those cards and the community cards. Players can call, raise, check or fold in turn, and the value of a hand is determined by its mathematical frequency. If a player makes a bet and no one calls it, that player wins the pot (all the chips bet so far). Poker can be played with 2 or more players and there are many different variants of the game.
There are a number of rules that vary between the variants. For example, some variants require players to make forced bets known as an ante or blind bet before they are dealt their cards. These bets are placed in the pot before the actual dealing of the cards, and may be made voluntarily by a player who believes that their bet will have positive expected value, or who is trying to bluff for various strategic reasons.
There are also a variety of tells in poker, which are indications that a player has a strong or weak hand. For example, shallow breathing, sighing, flaring nostrils, blinking excessively or staring at the chips are signs of nervousness and might indicate that a player is bluffing. If a player has a very strong hand, they will often bet large amounts to encourage other players to fold. In some cases, a player will put all their remaining chips into the pot, which is called going all-in.