Double or nothing

Double or nothing (UK often Double or quits) is a gamble to decide whether a loss or debt should be doubled or cancelled, if your opponent wants to play double or nothing you decide whether you want to play or not.

It refers to the potential outcome in a betting situation where the winner risks what has been won for a chance to double their winnings. If the loser of the initial bet loses the second bet then they owe double. For example, if one owes somebody a bottle of Coke from a bet and then places a "double or nothing" bet with the same opponent, they will owe two bottles of Coke if they lose and will owe nothing if they win.

In poker, a double or nothing tournament is an online sit'n'go tournament where the surviving half of players gets double the buy-in and the eliminated half does not receive any prizes. Double or nothing tournaments are mostly played by ten players (five players win) or six players (three win), although multi-table versions, such as for 20 players, exist. The rake in these tournaments is usually smaller than in standard sit'n'go tournaments. Some poker rooms also offer triple or nothing tournaments, where one third of the playing field gets paid.

In a regular poker sit’n’go it is correct to play with the intention of accumulating 100% of the chips in the game, thereby placing 1st and securing for yourself the maximum possible prize money. In a double or nothing poker sit’n’go it is now no longer relevant if you finish the game with 100% of the chips or only 1% of the chips, as long as you are still in the game once 50% of the players have been eliminated. Because of this difference in prize structure, a double or nothing poker sit’n’go requires significantly different poker strategy than a regular poker sit'n'go.

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Wikipedia