Poker is a family of card games played with a standard deck. It has several rules that differ from variant to variant, although the fundamental principle remains the same: players attempt to form the best five-card hand possible, ranking their cards from highest to lowest.

The highest possible hand is a full house (five cards of the same suit), which beats any straight flush. If two or more hands have the same straight flush, ties are broken by the highest unmatched card or secondary pair.

There are many different types of hands in poker, some more rare than others. Ranks are determined by their odds (probability), which is an inverse-relational function of the frequency of a particular combination of cards.

In a standard deck, there are thirteen different cards of each suit. A card is called a pair when it matches two other cards, and the highest possible pair is a quad.

Almost all poker variants involve some sort of betting interval before the showdown. In each betting interval, the player nearest the dealer’s left, as designated by the rules of that variant, must make a bet. Then, each player in turn must call the bet or fold.

In some poker variations, a player who does not wish to make a bet may “check.” This means that the player will not call but will remain in the game. This is also known as sandbagging. If all the players in a betting interval check, then the betting interval is over and all the players still in the game are eliminated.