The most common reply with grandmaster levels is actually 1... Pf6, usually followed by e6. But d5 is second, and is usually played later anyway if 1...Pf6. Some time ago I was trying to ignore the d5 move for as long as possible so that my opponent couldn't play his usual game. However I found the d5 move to be almost always nessecery in any opening.

Although this move renounces some of the main lines, and doesn't do much about White's early development, it can lead to interesting openings such as the Colle System or the Stonewall Attack.

I remember this move to be played in both the Stonewall and Colle system myself. A friend of mine on the chessclub likes to play Colle system, but I don't think he uses it 100% correctly. I think the Stonewall is a much better system. And yes, 2c4 is the most common move in this position.

I have to agree that black should find a plan that involves the move c5. Therefore the black knight should be going to d7, ofcourse only after the white squared bishop is moved. Black will create much more space if you think about a plan with c5.

Not bad, but more precise is to play 3.Nf3 (Colle system) or 3.f4 (Stonewall Attack) first. The reason is that Black could now play the annoying 3...Nb4. Although this means Black's moving a piece twice in the early opening, it does have some justification, offering to exchange the knight for White's 'good' bishop ('good' because it is less blocked in by pawns). White would then have to decide whether to allow the exchange, of lose time in his turn. Not a decision one likes to make so early in the game.

I agree with archduke piccole. White will later either move c3 or f4. Therefore the light squared bishop might actually be as much valuable as a rook. Nb4 threatens to take the bishop, andif there is an exchange white loses a very important piece!

Now we are heading into the Colle System. It's a line I like to recommend to developing players who like to attack. True, the queen's bishop is a problem child early on, but as the early plan is to build up behind the e-pawn and then push e3-e4, the expectation is the the then freed bishop will come into its own. Meanwhile, White can plan on playing 0-0, c3, Ncd2, Re1 and then e4. Always keep an eye out for any attempt to disrupt this plan, though.

Its an interesting plan but I'm not sure if I like it. The bishop should probably move to g7 but the pawn on d4 stops the scope of the bishop. This plan is good if you plan to play c5, but in this case if you move your bishop to g7 the pawn on c5 can't even be defended. Also in this system is c3, so there is likely to be a pawn on that spot for quite a while.

I think white should go for c3 soon.

Rather more solid is 5...Bg7. It doesn't look as though it does much on g7, but it actually does a great deal. For one thing it has a potential effect on the centre. For another it strengthens the weakness that would otherwise exist on the K-side dark squares. On h6, the bishop will have to be concerned about a future e3-e4 thrust (not playable yet).

Personally, I prefer 6.c3. but the knight move is quite playable.

I like c3 much better.

Another idea was 7.a3, to keep the knight out of b4. Normally I don't recommend this sort of move, but ...Nb4 could be really annoying, as White doesn't really want to exchange his d3-bishop for a knight, but moving it out of the way would lose time. Having said that, 7.b3 is quite unobjectionable, and is more likely to bring the dark-square bishop into effective action on b2 or possibly a3.

A harmless pin, easily dealt with by 8.h3. It is often - usually - better (but not always!!) to allow the pin before playing the rook-pawn forward, and then force the pinning piece to lose time.

8...Nxd4?? over-estimated Black's attacking chances, though the basic motif is quite a common one. The presence of the pawn on e3, able to swipe off the knight rather spoils the party, though.

What an interesting decision! Normally one would recommend retaking with the rook, to preserve the K-side pawn structure (10.Rxc1 Bxf3 11.Qxf3). But from c1, the Queen has access to h6, which might prove useful: 10.Qxc1 Bxf3 11.gxf3 whereupon White not only has the extra piece, but a fine K-side attack in prospect.

Probably Black might as well play 10...Bxf3 and hope to find counter-play against White's broken pawns.