Poker is a card game in which players bet on the strength of their hands. The goal is to make a winning five-card hand by using the two cards in your own hand plus the community cards on the table. Poker can be played in many formats, including cash games and tournaments. The game has become an international phenomenon, with many variations of rules and styles. It has also spawned several popular television shows and films.

In poker, every action – fold, call, check, or raise – gives information away to your opponents. They piece together these bits of information to build a story about you, determining whether you’re strong or weak and how likely you are to have the best hand.

Position has a huge effect on your starting hand range and strategy. The earlier your position at the table, the more risk you take because you have less information to work with before it’s your turn to act. However, this can be compensated for with good table image and betting patterns.

Professional players are experts at extracting signal from noise and integrating that information to exploit their opponents and protect themselves. They use a variety of tools and resources, including software to track their opponents’ behavior, to build behavioral dossiers on their opponents and even collect or buy records of other players’ “hand histories.” In addition to this, they use body language and verbal cues to communicate with other players.