Poker is a card game in which players bet on the relative strength of their hands. A player with a better hand wins the pot. Winning hands include pairs, three of a kind, and straights. A player can also win by bluffing. A good strategy includes making the most of winning hands and minimising losses from losing ones (called MinMax).

During each betting interval, one player, designated by the rules of the particular poker variant being played, puts into the pot the number of chips that is at least as many as the bet made by the player to his or her left. Other players may call the bet, raise it, or drop out of the betting. If a player chooses to drop out of the betting, they lose any chips that have already been put into the pot.

After each betting interval, the players show their cards. The best hand wins the pot. The players who are still in the hand then swap their cards for new ones. This is called “showdown.”

In the 1930s, von Neumann published his “Theory of Games” — a landmark work that laid the foundation for modern mathematical analysis of competitive interaction. His proof showed that a well-designed strategy for poker involves calling and raising with only a very small percentage of the strongest hands, and bluffing with some definable frequency. Since then, the field of game theory has continued to advance with the help of computers. The University of Alberta’s Department of Computer Science has made significant progress on the theory of poker, along with games as diverse as checkers, go, and StarCraft.