Poker is a family of card games in which players wager over which hand is best according to that specific game's rules in ways similar to these rankings.

Players form sets of five playing cards, called hands, according to the rules of the game. Each hand has a rank, which is compared against the ranks of other hands participating in the showdown to decide who wins the pot. In high games, like Texas hold 'em and seven-card stud, the highest-ranking hands win. In low games, like razz, the lowest-ranking hands win.

A straight is a hand that contains five cards of sequential rank, not all of the same suit, such as 7♣ 6♠ 5♠ 4♥ 3♥ (a "seven-high straight"). Under high rules, an ace can rank either high (as in A♦ K♣ Q♣ J♦ 10♠, an ace-high straight) or low (as in 5♣ 4♦ 3♥ 2♥ A♠, a five-high straight), but cannot simultaneously rank both high and low (so Q♠ K♠ A♣ 2♥ 3♦ is an ace-high hand).

Each straight is ranked by the rank of its highest-ranking card. For example, J♥ 10♥ 9♣ 8♠ 7♥ ranks higher than 10♠ 9♠ 8♣ 7♥ 6♠, which ranks higher than 6♣ 5♠ 4♥ 3♠ 2♦.

An ace-high straight, such as A♣ K♣ Q♦ J♠ 10♠, is called a Broadway straight, while a five-high straight, such as 5♠ 4♦ 3♦ 2♠ A♥, is called a baby straight, bicycle or wheel and is the best possible hand in ace-to-five low games (where it is a high card hand, not a straight).

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