Help with the Sicilian Defence - I need to understand those early pawn moves Why we often see many pawn moves in the Sicilian Defense? I would imagine that this harms the development of the black pieces. For instance, there is this line:

[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 a6 4. Nc3.
Yes, in the Sicilian black often falls behind in development, and that is a problem -- white often gets the chance to mount an attack.

But black has some compensation. After ...cxd4 Nxd4 he has two central pawns while white only has the e-pawn. In order to attack quickly, white often castles queenside and black can use the half-open c-file to start a counter attack. His a- and b-pawns can be used in a minority attack against white's queenside. He has no clear weaknesses.

It turns out, after a century and a half of trying to refute it, that that is enough to hold the balance. Indeed, the whole situation is also risky for white and that means it can give black more winning chances than normal (as well as losing chances).

But that was by no means obvious!

It's not an easy defence to understand, and it's debatable whether weaker players should play it.