Knock Rummy is a variation of the popular Rummy matching card game. Here's how to play:

Number of players: Two to five. Six players are possible, but that number of players reduces the amount of play.

Object: To knock and stop play when your count of deadwood or unmatched cards is less than your opponents'.

The cards: Standard 52-card deck. Aces are low.

Dealing: Two players, 10 cards each. Three and four players, 7 cards each. Five and six players, 6 cards each.

Melds: Melds consist of groups of three or more cards of the same rank or sequences of three or more cards in one suit.

Playing: Knock Rummy plays like Gin Rummy, except that players do not have to gin to stop play. A player can knock (rap on the table or say knock). Unlike Gin Rummy, the knocker's deadwood does not have to be less than 10 points. A player knocks after drawing the top card from the stock or the top card from the discard pile and before discarding. The knocker then discards and all players show their cards, separating melds and unmatched cards. Cards are not laid off.

Scoring: If you knock and have the lowest deadwood count, you win the point difference from all other players. If you knock and rummy (that is, all your cards are used in melds), you receive the point difference and a 25-point bonus from each opponent. If you knock and an opponent has the same amount of deadwood points, that opponent collects the point difference from the other players. If more than one opponent ties your deadwood score, they split the difference. If you knock and one or more opponents have less deadwood points, the opponent with the lowest score receives the point difference from each player. If they tie, they split the difference. Every opponent who has less deadwood points than you also receives a 10-point penalty from you. Before the first hand, players determine score needed to win game.