Chapter 6 (4) ... Ktb8-d7 (5) B-g5

The fact that White can develop his Queen's Bishop without difficulty while Black cannot do so has made the Queen's Gambit one of the most popular openings.

(5) ... B-e7 (6) P-e3 o-o (7) B-d3 P-b6 (8) o-o B-b7 (9) Pxd5 Pxd5 (10) R-c1

White is two moves ahead in the development, as Black has still

to move his c-Pawn before he can get his Queen's Rook into play.

In the meantime White can mobilize his King's Rook with Q-e2 and

Rf1-d1, with a view to opening the Queen's file by Pd4xc5.