"Jass" is a card game originally played in Switzerland. It is played with 36 cards. The card deck is divided into groups of 9 for each color. So there are 4 colors.
There are many different ways to play the game but the most common is to play it by four players. The most similar card game I know is the german "Skat" but it's still very different.
There are several types of card decks in switzerland. In central Switzerland and in the eastern part the deck is referred as the "Swiss" deck. It has colors named "Schellen", "Schilten", "Rosen" und "Eicheln". In the western part the colors are "Kreuz", "Ecken", "Herz" and "Schaufel". It is called the "French" deck.
Swiss deck description:
Colors: --------- "Schellen", "Schilten", "Rosen" und "Eicheln" Values: --------- As Koenig Ober Under Banner (10) Neun (9) Acht(8) Sieben (7) Sechs (6)
First the cards are shuffled and then distributed (closed) by the "distributor". He gives 9 cards to every player.
The player on the right hand side of the "distributor" now looks at his cards and decides which kind of game he wants to play. He will choose the one which best fits his cards. Meaning that he has to make as many points as possible together with his partner, the player sitting opposite to him. There are many different settings he can choose from. The standard choices are: "Obenabe" (top-down), "Undenufe" (bottom-up), "Trumpf" (special color)
But there exist many, many more. My friends and I even invented some new rulesets. If the player does not want to choose (he thinks he doesn't make enough points) he can hand the choice over to his partner - which is called "schieben". He now has to make a decision according to his cards.
The player now chooses a card and puts it (open) on the board. Now all other the players one after another have to play a card. When the fourth player played his card, the board is evaluated. The card with the highest value on the board "strikes" and the player who played this card can start the next turn.
The same procedure is repeated until all the cards have been played.
After all the cards have been played every team counts their points in their "strikes". The effective value of a card depends again on the ruleset. An "As" in "Obenabe" counts 11, but 0 in "Undenufe".
Both teams note their points on a paper or a shiver table. The team which first reaches 2000 points has won the game. After reporting, the next round starts. The distributor is now the one on the right-hand side of the former distributor.
That's it for the moment. For more information there are some links to good Jass info pages below.