A run is a series of three or more cards in the same suit, whereas a set is made up of three or four cards of the same rank but different suits. Two or morerummy apps with bonus players can play the game, & there are several variations with different rules & subtleties. A predetermined number of cards—usually seven or ten, depending on the variation—are dealt to players to start playing Rummy. One card is turned face-up to form a discard pile, while the other cards form a draw pile.