Bring-in

In the game of poker, the play largely centers on the act of betting, and as such, a protocol has been developed to speed up play, lessen confusion, and increase security while playing. Different games are played using different types of bets, and small variations in etiquette exist between cardrooms, but for the most part the following rules and protocol are observed by the majority of poker players.

Players in a poker game act in turn, in clockwise rotation (acting out of turn can negatively affect other players). When it is a player's turn to act, the first verbal declaration or action they take binds them to their choice of action; this rule prevents a player from changing their action after seeing how other players react to their initial, verbal action.

Until the first bet is made each player in turn may "check," which is to not place a bet, or "open," which is to make the first bet. After the first bet each player may "fold," which is to drop out of the hand losing any bets they have already made; "call," which is to match the highest bet so far made; or "raise," which is to increase the previous high bet.

A player may fold by surrendering one's cards. (Some games may have specific rules regarding how to fold: for example in stud poker one must turn one's upcards face down.) A player may check by tapping the table or making any similar motion. All other bets are made by placing chips in front of the player, but not directly into the pot ("splashing the pot" prevents other players from verifying the bet amount).

In general, the person to the left of the dealer acts first and action proceeds in a clockwise fashion. If any player has folded earlier, action proceeds to next player. In games with blinds, the first round of betting begins with the player to the left of the blinds. In stud games, action begins with the player showing the strongest cards and proceeds clockwise. If there is a bring-in, the first round of betting begins with the player obliged to post the bring-in.

If no one has yet opened the betting round, a player may pass or check, which is equivalent to betting zero and/or to calling the current bet of zero. When checking, a player declines to make a bet; this indicates that they do not wish to open, but do wish to keep their cards and retain the right to call or raise later in the same round if an opponent opens. In games played with blinds, players may not check on the opening round because the blinds are live bets and must be called or raised to remain in the hand. A player who has posted the big blind has the right to raise on the first round, called the option, if no other player has raised; if they decline to raise they are said to check their option. If all players check, the betting round is over with no additional money placed in the pot (often called a free round or free card). A common way to signify checking is to tap the table, either with a fist, knuckles, an open hand or the index finger(s).

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Wikipedia