Poker is a card game in which players place chips into the pot by calling (matching another player’s bet) or raising (putting more money into the pot than your opponent). The person who has the highest ranked hand when all the cards are revealed wins the pot, or all the money that has been bet during that round.

The key to winning at poker is understanding your opponents and working out what they might have in their hands. This is best done by analyzing their physical tells, which can reveal information about their cards through changes in posture or facial expression. It is also helpful to learn how to read their betting patterns, including when they call or fold and what type of bets they make.

In addition to learning how to analyse an opponent’s hand, a good poker player will also have a strong understanding of ranges. This is the number of different hands that an opponent could have, and it helps players to decide how likely it is that they will beat the other player’s hand.

Another important aspect of poker is knowing how to manage your bankroll and understand bet sizes. Bet sizing is a complex process that takes into account previous action, the number of players left in the hand, stack depth and pot odds. It is a key part of poker strategy and requires practice to master.