Swapping pieces is a basic chess strategy. If you swap the same pieces, it’s just a swap, and nobody is better or worse off. It’s harmless.
Harmless Swaps: Swapping a Knight for a Bishop, or a Bishop for Knight, is the most common exchange. And it’s harmless. Both Knights and Bishops are about 3 Pawns. Only at advanced levels of chess is the Bishop considered a little better than the Knight.
The Exchange: But be careful with some swaps. A Rook is worth 5 Pawns, which is more than a Knight or Bishop (3 pawns each). And the Queen is worth 9 pawns, but no beginner is going to swap a Queen for a Rook or a Bishop/Knight.
Swapping pieces is a good winning strategy if you are far ahead. If you’ve got extra pieces, you can just swap off the enemy’s remaining pieces, and then all they have left are pawns. This is called “swapping down” to a simpler position.
Swapping off the attacking pieces can also sometimes be a good defensive strategy. Especially if you can swap off the Queens. If you remove the Queens, the chances of you getting checkmated are much lower.
Related Chess Tactics
Read more about these related chess strategies: