Gin Rummy is a game in which two players compete to form consecutive runs of three or more cards or sets of three or four cards of the same rank. The goal of the game, which is playhow download play storeed over multiple rounds, is for players to "knock" when they think their opponent has more unmatched cards than they do. Gin Rummy's simplicity makes it a great way to introduce new players while still providing strategic depth for more experienced players. Up to six players can play Indian Rummy, another classic variation that usually uses two decks of cards.