7 card stud poker rules

Stud poker is any of a number of poker variants in which each player receives a mix of face-down and face-up cards dealt in multiple betting rounds. Stud games are also typically non-positional games, meaning that the player who bets first on each round may change from round to round (it is usually the player whose face-up cards make the best hand for the game being played). The cards dealt face down to each individual player are called hole cards (which gave rise to the common English expression ace in the hole, which suggests that one has something valuable that is not apparent to others).
Stud poker variants using 3 cards were popular as of the American Revolutionary War. Five-card stud first appeared during the American Civil War, and became very popular. In recent years, Seven-card stud has become more common, both in casinos and in home games. These two games form the basis of most modern stud poker variations.
The number of betting rounds in a game influences how well the game plays with different betting structures. Games with four or fewer betting rounds, such as five-card stud and Mississippi stud (described below), play well with any structure, and are especially well suited to no limit and pot limit play. Games with more betting rounds are more suited to fixed limit or spread limit. It is common (and recommended) for later betting rounds to have higher limits than earlier ones. For example, a "$5/$10 Seven-card Stud" game in a Nevada casino allows $5 bets for the first two rounds and $10 bets for subsequent rounds. Also common is to make the final round even higher: a "$5/$10/$20" game would allow $20 bets on the last round only. Another common rule is to allow the larger bet on the second round if there is an "open pair" (that is, at least one player's upcards make a pair). Some casinos (typically in California) use the smaller limit on the first three rounds rather than just the first two.
It is a common convention in stud poker to name the betting rounds after the number of cards each player holds when that betting round begins. So the bet that occurs when each player has three cards is called "third card" or "third street", while the bet that occurs when each player has five cards is "fifth street". The final round, regardless of the number of betting rounds, is commonly called the "river" or simply the "end".
The variations described below assume that you are already familiar with five-card stud and seven-card stud, and with the game play of poker in general.
Some rule variations can be applied to almost any game, and combinations of these variations can be used to create ad-hoc games. These include roll your own, rollouts, blind stud, and twist rounds.
Any game can also be changed by adding one or more jokers to the deck to act as wild cards, or by designating certain other cards as wild. Some specific common variations include Low hole card wild, in which each player's lowest-ranking downcard (and all other cards of that same rank) are wild in that player's hand only, and Follow the queen, in which each time a Q is dealt face up to anyone, the next face up card (and all others of that rank) become wild. The usual practice in the latter case is that if a second Q appears among the upcards, the previous wild card loses its status to the new one.
One can also vary any stud game by dealing extra downcards and requiring either that one or more hole cards be discarded at some point in the game or adding a restriction on how many of those hole cards may be played in the final hand. For example, five-card stud can be modified by dealing each player an extra downcard at the start of the game, adding the restriction that each player may only use one of his two downcards in his final hand. This game is called Crocodile stud. Likewise, seven-card stud can be modified by dealing each player three downcards instead of two on the first round, but adding the restriction that a player may use no more than two of those cards in his final hand (called Buffalo stud; if the extra hole card must be discarded after the first betting round, then it is Australian stud). If playing one of these games without the requirement to discard the extra hole card at some time during play, it is recommended as a practical matter to ensure compliance that each player physically discard one hole card immediately before showdown, before revealing the "live" hole cards (so that there can be no confusion about which cards were down).
Variations can be made by eliminating betting rounds, dealing more than one upcard at a time for one or more rounds. For example, Mississippi stud (see below) is basically seven-card stud with the second betting round removed, and the last card dealt face up instead of face down. Further adding an extra hole card as above makes it Murrumbidgee stud.
Games that mix stud-like rounds with community cards are discussed on the Community card poker page. In general, one can mix upcard rounds with community card rounds in many ways. See in particular Oxford stud on the community card game page.