The Caro-Kann Defense
Assuming that you play white in the Caro Kann opening game, you can start the game with the normal moves: 1.e4 c6, 2.d4 d5, 3.Nc3 dxe5, 4.Nxe5 Nd7. White next moves Qe2, which can be a bit deceptive for black, if your opponent is preparing for a particular position. Usually, in such a case, black would tend to get the knight at d7 out-of-the-way and move to b6 after which white can play Nf6#. This is a trap which follows the opening moves and white varies his moves in such a way that it keeps his queen behind the knight. Black falls into this trap.