I don't understand why in many posts I see that say for example that a najdorf sicilian requires alot of theory or else you will get destroyed. I don't understand this. I don't play the sicilian, my concern is beating it with white. Isn't it enough to know that I want to launch a kingside attack with my f and or g pawns and pieces while preventing black from getting counterplay? honestly I haven't played in many main line sicilian games though.

Because it has a lot of sharp positions where both sides are often hanging on the precipice; if Black falters, he can get mated quickly, and if White has a lapse, he'll lose the initiative/attack and he's usually in for a long and dreary endgame.

If theres any opening that needs no theory, I'll play it.

WOOOOT 2 hrs a week more time

I play the Sveshnikov Sicilian and it's very tough. Before every tournament game, if I'm black, I take out my Sveshnikov book and study for maybe 10 minutes. There are so many lines in the Sicilian, and like tonydal said they're very sharp. I usually have trouble playing online blitz with someone who knows what they're doing against my Sicilian and end up getting run over in the center.

In the sicilian many positions are unbalanced and dynamic, and it's difficult to assess them correctly over the board without knowing some thematic ideas, as calculating them "live" is often very difficult for most players.

That s the poisened pawn variation of the Najdorf right?Black must play ultra sharp this variation.

It depends so much on the standard at which you play. At a beginner and even intermediate level where games are won and lost by who makes the least blunders, It is not so important to understand lines 30 moves deep etc. It is likely that if you learnt such lines, your opponant will play a sub standard move that leaves your preperation very early on, and then it becomes a question of if you already have the skill and experience to even notice this and then how to exploit it!

At expert level and beyond it is excepted that your opponent will know how to exploit any weakness and how to finish off games. It becomes much more important therefore to be sure that the move you play is the best move. The way to do this is to study previous masters games and try and understand why "Book Moves" are better then the one you might have thought of, and then learn them to save huge amounts of OTB calculation in often sharp and complex positions. 

I have played the Sicilian since I was 10yo and wouldn't put anyone off playing it - unless you are regulaly playing people much much better then you, then you are fine to rely on your general chess skills and not get bogged down in learning anymore then first few moves and responses. As you imporve and play better players you will notice the same positions arriving over and over again, it's at that stage you want to be starting some study and learning what others have already found when they reach those positions! This can be said as both White and Black.

Don't be scared of it, get stuck in and as you improve and keep running into the same problems you will know what and when you need to study a bit more!

One other point about positions in most mainline Sicilians not mentioned is that many of the moves are rather counterintuitive for both sides. Knowing theory really helps since trying to reproduce the positions or moves would be extremely difficult and/or time consuming if not impossible.

This is why I don't play Sicilian too much.  I don't want to study too much, so I play offbeat openings, so my opponents cannot throw so many traps at me that they know about.  I do better with offbeat openings.

ya that is posioned pawn varition black is peferctly ok kasparov and anand have played it as black

does the Bb5 variation also require alot of theory?

you know when you play maybe 1.e4 e5? then maybe you move 2.Nf3 and he thinks " oh i must protect pawn with 2...Nc6 and then you throw out 3.Bb5 pinning knight threatening to take pawn again and so on? you can play like "oh if he does that then i do that and if he does that then i do that. you can get a long way by simply understanding whats going on here without to much theori.

well in the sicilian you cant do that because its a race on each side of the board and the first player to the goal wins. when you see who is winning the race its most likely at the end of the race and its probably to late to do anything about it so you pretty much need to know it by doing your homework in the sicilian. in addition you must check all the time if the center can be blown open and who benefits from it on every move. complicated stuff to get right over the board sometimes. i hope this helps:)

And then we sit down to play the game and I play 1.d4

The only thing I don't like about the Sicilian is that many people I play against (my average opponent's rating is 1460) don't play 3.d4 - instead they play 3.d3 or 3.Bc4 4.d3 . This means I don't get to play many proper Sicilians and when I do, my opponent knows the game better than me.

What's the best way to "punish" people who don't play 3. d4? (assuming the alternatives are bad moves)

I think a better way of characterizing moves other than 3.d4 would be "not a serious try for an advantage" -- talking about 3.d3 or 3.Bc4 with plan of 4.d3.

I think you should just play to control the center, the usual stuff. If Bc4, typically you would play e6, and then if d3, you can play a6 where they'll probably play a4. You can play a black setup similar to the Closed Sicilian, where you make these moves:

c5, Nc6, d6, e6, Nge7 g6, Bg7

I know that sicilian players would hate me to say it, but are the open sicilians truly sound? It gets very complicated, but ultimately I think white will be ahead in the race. On fritz it always says something like .7 when I play through many book moves and like in the dragon when white plays the yugoslav attack I'm sure he has a quicker attack and black will probably absolutely need to find the concrete solutions to these problems by studying the moves but even then if white plays his correct moves I think his attack comes first. And also the najdorf isn't favored by the computer either and it does look as if black sure is wasting alot of time. Everyone calls the sicilian as a sound way to fight for the initiative but can he really get equal chances when white has all of those pieces out? Of course white will probably not play the best moves but the fact that white can get some very dangerous threats at least shows how risky a sicilian can be for black. The up side is just that if white makes a mistake black has his counterplay, but you can't just hope for that and expect to win all the time! The sicilian is dangerous for both sides (open variaiton) but I can see why the computer prefers white's position so much. This lack of solidity if white plays correctly is why a computer thinks the best strategy with black is to hold on for the draw with ...e5 and safely punish a potential mistake from white but not as much. I know people make many mistakes, but seriously does it have to be favored this much by even GM's?

That's what I usually play - followed up with a6, b5. I guess I'll keep it up then, thanks!

When you play the Sicilian 1.e4 c5 if whites play 2.Nf3 the normal continuation to prepare the d2-d4 pawn move, then to avoid all of the complications of the myriads of combinations for black , then play d6, a Scheveningen variation that will give you an equal chance of winning. 

White is then reduced to play 3.d3, 3.Nc3, 3.g3. Playing 3.d4 is likely to happen and plays an open Sicilian game. Black plays 3....cxd4  follows 4.Nxd4 Nf6, white still had an opportunity to transpose here in the Smith-Morra gambit by playing 4.c3 learn the lines if so. 

5.Nc3 best way to defend the pawn though it does obstruct the c2 pawn and preventd it to move to c3 or c4.

You are still not out of the woods yet as many upcoming moves require a knowledge of what to play in particular, for example after 5...Nc6, white can play the Keres attack 6.g4!? giving whites an opportunity to win.

When playing the Sicilian as a beginner, give your self a chance to get a draw as you are playing against someone of your own level and you might get

The reason knowing the theory is so important in the Sicilian is its sheer popularity.  It has been one of the favorite defenses to 1 e4 since at least the 1950s at even the highest levels.  The top grandmasters of every generation have worked out many of the main lines to move 25 and beyond.

If you are playing a Sicilian from either side against someone who is more familiar with the theory, even though they may be an objectively weaker player than you, they may exploit your errors to gain a winning position known to theory - without having to actually "play" you at all, by just remembering what the GMs do.

So often in the Sicilian, too, the correct move is counter-intuitive:  the "simple" developing move may lose by force because it squanders a tempo you need for what you REALLY should be doing, or fails to block the opponent's known plan.  And unless you follow the current GM scene closely, you might miss a game that changes the evaluation of a line completely overnight. 

Any sharp opening is subject to such rapid change, too, of course, but the Sicilian's huge popularity (check any large database for distribution of games by opening) makes it more likely your opponent will have specific knowledge of lines which run very deep than in some other.

If you want to play it - and it is the greatest counterattacking defense in chess - LEARN IT.  Practice in club games and in casual internet contests, and play a good number in all the major lines until you feel comfortable in the various positions. 

IMO, the reason for the current popularity of what we used to consider "irregular" lines for White (like the Closed, 3 c3, 3 Bb5, Gran Prix, etc.) is that White players often don't want to spend the amount of time needed to learn and keep current with the main lines of the Sicilian, but want to continue playing 1 e4.  White can still pose some opening problems for Black with any of them by virtue of his move in hand - but nowhere near the critical situations which arise with regularity in many of the traditional main lines with 3 d4.

Yeah - extreme sharpness (in some lines - not all of them) combined with very rich positions (I mean, they're extremely sharp, have been worked on for decades and still they're not worked out entirely) combined with popularity.

But don't forget that this holds only for some lines - Bg5 and Be3 Najdorfs, Yugoslav attack Dragons, that sort of thing. If black plays the Accelerated Dragon, theory is much less important. Similarly, white could play quiet Be2 or g3 systems, which are still dangerous for black, but need far less theory for the white player.

So in that light, the popularity of the antis (that give black easy equality) is a bit odd. On the other hand, currently I play 2.c3 myself, so who am I to talk :-)