Gin Rummy is a card game invented about 1909 as a variation of knock rummy. It became a fad in the United States in the 1940's and is still the most popular of all two-handed card games.
Two, three, four, or more in even numbers may play. However, it is basically a two-handed game. When three play, one player is usually inactive. When four play, two two-handed games are played simultaneously and the scores of partners are combined at the end of each hand. A standard 52-card pack is used. The cards rank from king (high) down to the ace. Face cards are worth 10 points, aces 1 point, and other cards their face value.
The dealer deals his opponent and himself ten cards each, one at a time, facedown, and places the rest of the pack face down on the table to form the stock. The top card of the stock is turned up and placed beside it as the upcard and begins the discard pile.
The nondealer has the first chance to take the upcard. If he refuses, the dealer may take the upcard; if the dealer refuses, the nondealer begins play by drawing the top card from the stock. In his turn, each player must draw either his opponent's discard or the top card from the stock, and discard one card faceup. Play continues until either player knocks.
A player may knock when the value of the unmatched cards in his hand, after he discards, is 10 points or less. He need not knock when able to do so. When knocking, he spreads his hand, arranged in matched sets and unmatched cards, and discards one card face down. The opponent then spreads his matched sets and lays off any other cards that match the knocker's matched sets. When a player knocks with a count of zero, he is gin and his opponent may not lay off.
Neither of the last two cards in the stock may be drawn. If the player who draws the 50th card discards without knocking, his opponent may refuse the discard and the hand is a draw. The player who dealt the hand deals again.
Object of the Game
The object of play is to form matched sets of three or four of a kind and sequences of three or more cards in the same suit. For example, K-K-K, or Q-J-10-9 of hearts.
At the end of a hand, if the count of the knocker's unmatched cards is less than his opponent's, the difference in counts is scored to his credit. However, if the opponent ties or beats the knocker, he has undercut him, and he wins the hand and scores a 25-point bonus plus the difference in counts, if any. If the knocker gins, he scores a 25-point bonus plus the count of his opponent's unmatched cards. It is impossible to undercut a gin hand.
The first player to reach 100 points wins the game. He adds to his score a 100-point game bonus. Each player then adds to his score 25 points for every hand he has won. This is called a box bonus. The scores are then added, and the player with the higher total wins the difference in counts. If the loser has not won a hand during that game, the winner doubles his entire score for shutout, which is also called Schneider, skunk, or blitz.