Queens Gambit Declined
Playing 2...e6 releases Black's dark-squared bishop, while obstructing his light-squared bishop. By declining White's temporary pawn sacrifice, Black erects a solid position; the pawns on d5 and e6 give Black a foothold in the centre. The Queen's Gambit Declined has the reputation of being one of Black's most reliable defenses to 1.d4. In this situation, White will try to exploit the passivity of Black's light-squared bishop, and Black will try to release it, trade it, or prove that, while passive, the bishop has a useful defensive role.