Gin Rummy requires two players and a standard deck of 52 playing cards. Aces are valued at one point, face cards are worth 10 points each and the numbered cards are worth the value of the card itself. The game ends when a player reaches 100 points.
The game begins with the dealer distributing 10 cards face down to each player. The 21st card is set face up to start the discard pile. The rest of the cards sit face down aside the discard pile. This is the stock pile. Players then take turns either picking up the top card of the discard pile, or the top card from the stock pile. The acting player then plays an unwanted card from his hand to the discard pile. The goal of each player is to build a hand with a series of runs and sets. A run is a collection of consecutive cards in the same suit. An example of this is the 10, jack and queen of clubs. The minimum collection of a run is three cards, though there can be more if applicable. A set is a collection cards with the same rank. An example of this is having three or four aces.
The hand ends when a player either knocks or goes gin. A knock is when a player has less than 10 points of deadwood, or non-melded cards. Going gin requires the player to have no deadwood in the hand. The meld for both players is displayed, and the deadwood of both players is counted. The difference in deadwood determines the score for the player that knocked. Going gin awards an automatic 25 points to the player, plus the value of the opponent's deadwood.