304, pronounced three-nought-four, is a trick-taking card game popular in Sri Lanka, coastal Karnataka, Tamil Nadu and Maharashtra, in the Indian sub continent. The game is played by two teams of two using a subset (7 through Ace of all suits) of the 52 standard playing cards.
304 is a strategic game, as opposed to one that is based on luck, and everything can be exactly calculated.
The cards are dealt by the dealer to all four players in a counter-clockwise manner (as opposed to games like Euchre, which circle the table clockwise), each getting four cards in the first round. Then the player to the right of the dealer looks at his cards and picks out a trump and places it face down on the table. He then shouts out a score for his team to score, which he trusts he can win with the cards he has. Then a member of the opposing team can pick their own trump, and must pick a score higher than that was named before for his team to score. When a score is agreed the rest of the cards are distributed and the game is started.
The game is played similar to the standard rules followed, where the players answer the suit played. But if they don't have the particular suit, then they can try to guess the trump by passing a face down card to the player who has closed a trump card. If he or she guesses it right then she gets the hand or else the game goes on.
Points are scored according to the points shown in the table. After all the hands are completed, if the team has scored the required score they win.
So, depending on which version of the game you are playing the total number of points in the whole set of cards is either 304 or 30.4, hence accounting for the name of the game.
In this version, the concept of marriages is introduced, which consists of a K and a Q of the same suit. After the first hand won by any party, partner possessing the "Marriage" must show it to all. Trump marriage carry 40 points whereas non trump marriage carries 20 points. If the bidding group shows the marriage, their bidding gets reduced by that many points. If shown by opponents, bidding is increased by that many points.
Last tricks also count 10 points towards the making or breaking of the bid.
The cards: All cards 7 through A of all the suits are used in the game, and the hierarchy is unique to the game. It runs as J, 9, A, 10, K, Q, 8, 7. The points are same as those in the alternative version as given in the table above.