In all poker games, if more than one player remains after the last betting round, all of the players expose and compare their hands to determine the winner or winners. This is called the showdown.
All players should expose their hands immediately, and each player is entitled to see every other player's hand. Because exposing a losing hand gives information to an opponent, many players are reluctant to expose their hands until after their opponents have done so. To avoid this deadlock, casinos often have a rule specifying which player is required to show his hand first (usually the one who made the last raise), and then each player after that is required to show his hand in turn. Some players may choose to discard their hand and forfeit their interest in the pot rather than show their losing hand. If this happens, any other player involved in the showdown may demand that the hand be shown.
Because the act of folding a losing hand rather than showing it down is so common, some players can take advantage of others who do this with a rare play called a "call-bluff". For example, if you know that a player always folds rather than showing his hand if he was bluffing, you might call his last bet even with a hand inferior to the one you suspect him of bluffing with, expecting that he will simply fold before he sees that you don't actually have him beat.
