Tarrasch Defense is a chess opening with the ECO code D32. It goes 1. d4 d5 2. c4 e6 3. Nc3 c5. White opens with 1. d4 (the queen's pawn) and Black answers 1... d5. After 6 moves it is White to move. The lesson on the board explains every move of the line and lets you play it yourself; it is free.
The moves
1. d4 – White plays the pawn to d4
1... d5 – Black plays the pawn to d5
2. c4 – White plays the pawn to c4
2... e6 – Black plays the pawn to e6
3. Nc3 – White plays the knight to c3
3... c5 – Black plays the pawn to c5
About the Tarrasch Defense
Against the Queen's Gambit, Black plays ...e6 and ...c5, accepting an isolated d5 pawn for free, active pieces.
The isolated d-pawn gives Black space and open lines for the pieces.
White blockades d4 and trades pieces, hoping to win the weak pawn in the endgame.