In general, early bishop moves to those positions such b5, b4, g5 and g4 serve the purposes of pinning the knight to the queen or king OR of preparing to exchange the knight off. It's hard for us to comment in a general manner beyond that in a short answer on the forum, because it involves positional ideas such as central control, strong/weak colour complex (resulting from a player giving up a bishop) and pawn structure. In the Ruy, White is threatening Bxc6 and Nxe5 winning a pawn on any Black move that doesn't reinforce the knight on c6, defend e5 or force Bb5 away. White can never win a pawn if Black replies reasonably, but White's plan will change based on Black's reply. For example, if Black goes 3.. d6 defending his e5 pawn but creating a pin on himself, then White seizes the center with 4. d4 when 4.. exd4 5. Qxd4 Bd7 6. Bxc6 Bxc6. White queen controls the center and targets g7, but has lost the longterm advantage of the bishop pair. 3.. a6, Black's best move objectively, is too complicated for anyone to comment on, probably.
Early game: Why pressure knight with bishop?
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Hey guys, just had a quick question. Why is the best move sometimes moving your bishop to apply pressure to opponent knight? What is the purpose of this move?
For example moving Bb5 to put pressure on Nc6 in Ruy Lopez. And in any other openings I do sometimes a computer analyzes that as the best move.
Is it because knights are very valuabe early on? Pinning the knight and pawn to block king? It also just seems like a lot of the time a pawn will move up to attack the bishop and the bishop will flee.
So, what is the importance of this move? Thanks everyone!