Schnapsen is a point trick-taking game for 2 players using a 20 card deck consisting of ace, ten, king, queen, jack of the four suits. (Value and rank are the same as in Skat and Schafkopf.) Each round players are dealt five cards, replenishing from stock after each trick, with one turned up to indicate trump. The goal in each deal is to accumulate sixty-six trick points, where the card values are A=11, T=10, K=4, Q=3, J=2. The suit led does not need to be followed until the stock is closed or exhausted, at which point suit must be followed, the trick must be won if possible, and you must trump if you cannot follow suit.
Depending on the margin by which a player wins the deal, that player scores 1-3 game points. A player who reaches 7 game points wins the whole game (called a "Bummerl"). Detailed rules can be found at http://psellos.com/schnapsen/rules.html.