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In chess, an exchange variation is a type of opening in which there is an early, voluntary exchange of pawns or pieces. Such variations are often quieter than other lines because the early release of tension precludes any surprise tactics or sharp, forcing lines. Thus, a player with the white pieces may choose an exchange variation when playing a higher ranked opponent, as a means of obtaining a draw.
Not all exchange variations are quiet; in the Grunfeld Defense the exchange variation is regarded as the sharpest and most aggressive option, since it allows white to build up a massive pawn center while Black tries to turn it into a weakness. The exchange variation of the Queen's Gambit Declined often involves kingside attacks by one or both sides.
Exchange variations involving the exchange of pawns often lead to symmetrical central pawn structures. Such variations exist in the Queen's Gambit Declined, the Caro-Kann Defense, and the French Defense, among others. Exchange variations in which pieces are traded are present in the Ruy Lopez and the Grunfeld Defense.
The diagram at right shows a position in the exchange variation of the French Defense, after the moves (in algebraic notation):
The position is completely symmetrical and White's advantage is limited to his right to move.