Why are games more likely to last 60, 80 and 120 moves?

This is due to time control:

  the World Chess Federation FIDE sets a single classical time control for all major FIDE events, according to the handbook: 90 minutes for the first 40 moves, followed by 30 minutes for the rest of the game, with an addition of 30 seconds per move

Other time controls are used, but are usually based on multiples of 20 moves.

Mikhail Botvinnik, a former world champion, once said:

  The amount of errors made at time control are legion

So gross errors accumulate around the 20th, 40th, 60th etc. move, and so would resignations, loss on time and draw offers.


Why Black should play Max Lange attack, when its favorable for white only.?

I hope you are talking about the below line . " 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.d4 exd4 5.0-0 Bc5 6.e5 "

The Best response to the above line from Black is 6) ..d5! .

7.exf6 dxc4 8.Re1+ Be6 9.Ng5 Qd5 (9...Qxf6?? 10.Nxe6 fxe6 11.Qh5+ followed by 12.Qxc5 is a notorious trap) 10.Nc3 Qf5 (10...dxc3?? 11.Qxd5 wins, since 11...Bxd5 is illegal) 11.Nce4 0-0-0 with complicated play.

True the Theory of max lange extends long but it is refutable from Black side . Black needs to be extra cautious to avert White's Activity . Black should try castling Q-side . One line goes as follows

"1. e4 e5   2. Nf3 Nc6   3. Bc4 Bc5   4. d4 exd4   5. O-O Nf6   6. e5 d5   7. exf6 dxc4   8. Re1+ Be6   9. Ng5 Qd5   10. Nc3 Qf5   11. Nce4 O-O-O   "

If on move no 9)White captures the g7 pawn then advantage goes to Black's side .

" 1. e4 e5   2. Nf3 Nc6   3. Bc4 Bc5   4. d4 exd4   5. O-O Nf6   6. e5 d5   7. exf6 dxc4   8. Re1+ Be6   9. fxg7 Rg8  "

The White Player is the Man with the Plan and he needs to remember each move precisely else one incorrect move and the Tables will turn towards Black side .

The most aggressive line is " 1. e4 e5   2. Nf3 Nc6   3. Bc4 Bc5   4. d4 exd4   5. O-O Nf6   6. e5 d5   7. exf6 dxc4   8. Re1+ Be6   9. Ng5 Qd5   10. Nc3 Qf5   11. Nce4 O-O-O   12. Nxe6 fxe6   13. g4 Qe5   " . Here the Game depends on who is a better player .

If you are still unsure & afraid to play Max Lange then I would suggest that you try Philidor Defense as Black which is safe and does not involve too many gambits line .

In top level Tournaments you can rarely see Max Lange nowdays .


What is considered the current main line for Black against the Smith-Morra gambit?

Most reference books will give the main line as

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 Nc6 5.Bc4 e6 6.Nf3 d6 7.0-0 Nf6 8.Qe2 0-0 9.Rd1 e5

Followed by either 10.Be3, 10.h3, 10.Bg5, 10.a3 or even 10.b4.

They usually evaluate this 'main line' as a dynamic equality.

Repertoire books often offer other ideas for Black (with...g6, or ...Ne7, or ...Bb4, or ...a6 and ...b5, or 3..e5 or refusing the gambit right away).

[fen ""]
1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 Nc6 5.Bc4 e6 6.Nf3 d6 7.O-O Nf6 8.Qe2 Be7 9.Rd1 e5


Historical origin of the queen as a chess piece

A basic problem is to define terms and criteria.  What is needed to 'have introduced chess' in Europe? Is it enough to find chess men mentioned in donations or bequests?  Or do we need proof that the rules of the game were known?  Or perhaps even that they were used to play according to those rules?  Is an introduction that we find one mention?  Or do we need to have a significant number of people with chess pieces, or playing chess or whatever?

Murray's  A History of Chess mentions wills from the family of Counts of Barcelona, at least one of is dated to early 11th century, thus before Alphonso X. So Alphonso appears to be out as point of origin. He also notes multiple mentions of the game during the 12th century (i.e. in the 1100's), adding to the problem of having Alfonso introducing the the game, except in very limited sense. (The nordic game 'skak-tafl', which is usually taken to be chess, was played in 11th and 12th century -- which may be an added problem in connecting Alphonso X with the game.)

There are also indications that the games was known to Europeans even earlier, outside Europe.  If that is correct, it certainly opens for other vectors of transmission into Europe than through Spain.  Even though the game is more likely to be found mentioned in writing in relation to royalty, high nobility or priesthood, (as they were mainly those who left written documents) there seems to be no clear reason why tradesmen and sailors anywhere necessarily must have been ignorant of the game.

As to the name of the queen itself ... I'll leave that for others. Murray suggests that the name of the piece we call Queen was part of the Europeanization of the game: in Europe, a queen was perhaps the only generally recognized piece to have a natural place beside the king. Besides 'Queen', version of 'ferz' were also used -- there seem to be Spanish sources using the term 'alfferza' as well as connecting it to the idea of a standard-bearer.  If Spain could be shown to be the sole or main point of entry of chess into Europe, then the naming of the queen would probably originate in Spain as well.  But until that has been shown definitely, origin of terminology is probably best treated carefully.

But again, perhaps, the question of what the question really is may need to be asked.  Yalom connected the modern queen, with its added powers of movement, with Isabella, not the old queen piece.


Why is Chinese chess (xiangqi) harder for computers than international chess?

As far as I can see there is no fundamental difference between chess and xiangqi that would make xiangqi more difficult for a computer.

The state space complexity of chess is somewhat higher, whereas the game tree complexity of xiangqi is higher. Also the branching factor of xiangqi is 38 compared to 35 for chess, not much of a difference.

I suspect that while chess has been in the focus of computer research for many decades, there just weren't the same resources devoted to optimising xiangqi engines.

Possibly the slower game (because of the weaker pieces) requires the calculation of longer variations (see game tree complexity), increasing the hardware requirements, but I think that should only be a minor difference compared to demonstrably more complex games like shogi or go.

It is a bit difficult to find out precisely how strong xiangqi engines are right now, but any of the two factors would explain if they lagged one or two decades behind.


Method to study chess puzzles way above your level

Chess puzzles (and to a large extent playing chess) are based around recognizing certain patterns or motifs which help you to quickly assess a position and to visualize potential lines without the need to calculate move by move in your head.

Chesstempo has a good list of tactical motifs and positional motifs. It is important that when you solve problems (or when analyzing your games) that you realize which motives (usually there is more than one) apply to this problem. If you cannot solve a problem on your own it is fine to look up the solution or to get help from a computer, but make sure you understand the solution (i.e. match them to motifs/patterns). Again chesstempo is very useful for this as it shows you the motifs of each problem as "tags" (after you solved it or after you failed to solve it).

Once you have built a repertoire of patterns/motifs in your mind you should have a good basis to solve more complicated problems as well.

Another factor could be visualization when calculating long lines, but there is not much you can do about it other than concentrating, playing games, analyzing games, solving puzzles.... basically everything you should be doing anyway.


Did Karpov really only wash his hair when he lost?

This story has a very long pedigree going back much further than the GingerGM.

The earliest reference I can find on the internet is from a November 1985 report on the Karpov v Kasparov match in People.com's archive - http://people.com/archive/anatoly-karpov-is-straining-in-vain-to-keep-his-world-chess-title-from-gary-kasparov-vol-24-no-20/

  Unlike his extroverted rival, Karpov — who has all the appeal of a
  cold fish —ignores the crowd. When he intends to play aggressively, he
  emerges onstage clad in a black suit. In keeping with a chess
  superstition, he hasn’t cut his hair during the current match. Indeed
  he seldom seems to wash it, and he has been losing weight to boot.

Paul Hoffman (https://paulhoffman.wordpress.com/2007/11/19/superstition-in-chess/) says he mentions it in his book "King's Gambit"

  In King’s Gambit, I write about superstitions at the board. Players
  who insist in wearing their lucky T-shirt or underwear or keeping
  score with the same special pen. World champion Anatoly Karpov was
  famous for not washing his hair when he was on a winning streak.
  Grandmaster Nigel Short said of Karpov: “Unfortunately, he had long
  tournaments where he never lost a game—the guy got greasy.”

The English Chess forum brought this up in a thread on "Poor Taste" - http://www.ecforum.org.uk/viewtopic.php?t=2045&start=30#p36136 - back in 2010.


I do not think that you will ever get a definitive answer. I did find an interesting article of a dedicated etymology site here.

I will quote part of it here:

  By the Oxford English Dictionary’s (OED) reckoning, the earliest
  record of draw, as in a contest that ends with no winner, comes in
  reference to an 1856 US chess match. Over the next few decades,
  writers marked off draw with quotes or italics, which shows the word
  was novel. The word was familiar by the 1870s.

  This draw is short for draw-game, which the OED finds for a “tie” by
  1825. A draw-game, in turn, is a variation on a drawn battle or drawn match. The OED dates drawn match to a 1610 letter from English
  diplomat Sir Dudley Carleton: “It concluded, as it is many times in a
  cock pit, with a drawn match; for nothing was in the end put to the
  question.” (Before pilots occupied them, game-cocks fought in
  cockpits.)

  Why such a battle or match is characterized as “drawn” is unclear:
  Indeed, etymology often ends in draws. Drawn may be clipped from
  withdrawn, as in fighters who have withdrawn from the battlefield.
  Withdraw, “to take back or away,” features an old and original sense
  of the preposition with, “against,” even though it now, ironically
  enough, means “together.” Draw, meanwhile, is related to drag. And
  withdraw itself might be a calque, or loan translation, of Latin’s
  retrahere, “to retract.”

That is probably as close as you will get.


Is there a Web Service available for 6-piece endgame tablebases?

We can find several website giving 6-piece endgame tablebase, the tricky part is probably the way you want the information back.
Here is 2 examples of endgame tablebase :

http://www.shredderchess.com/online-chess/online-databases/endgame-database.html
http://chessok.com/?page_id=361

In both of this example you can ask a position by putting FEN code, so there is probably a way to use it as a webservice. (Perhaps you'll have to use a script)

Also another suggestion, on the link section of http://en.wikipedia.org/wiki/Endgame_tablebase you can find Nalimove database and try to make it communicate with your software.


What should I do about the dilemma of castling early?

I think you outline the balance well, that is what it is. You are talking about attempting to misdirect an opponent. In any game, misdirection is a dangerous tactic that takes skill to know when to make your move.

If you can get to know your opponent you can try to judge how they will move on you. If you are dead set on castling to a particular side, and your opponent knows that, then delaying doesn't help you at all.

The best solution is to remain flexible and let your opponents over or under steps dictate which tactic to use. This is as true for when to castle as anything other tactic.


what are some good openings with a trap to play *against* beginners?

There is none. You should play the openings where you are stronger, and you should play normally as if you were facing a strong opponent, because if you let your opponent get some kind of messy position you are risking losing yourself.

All I can say is to play good moves, sooner or later your opponent will blunder something.


Can I play chaturanga on any of the main chess sites?

You answered your own question, with 1) and 2) being the main causes!
I don't know about 3), tbh, but it seems at least somewhat plausible (although stalemate was also a win in chaturanga so who knows!).
You say that it's not on main chess sites, but chess.com at least has it as a playable variant- can't speak for how easily you'll find a game there however.
It's also presumably not trivial to code the game, which is probably another reason why.


If you have a demanding job, studying in the evenings can be difficult. You can even have the feeling that your brain simply says, "No".

Personal Productivity Stack Exchange has many questions related to concentration, and many of the answers there should be relevant to chess training:

Using the pomodoro technique: divide tasks or study session into sequences of intervals of roughly 25 minutes. Take a break after each 25-minute interval. This is one "pomodoro". Take a longer break after four pomodoros. (I'm just covering the basics of the technique here, obviously. One of the questions that mentions the pomodoro technique is My thoughts distract me, how do I keep my focus?.)
If your mind still keeps wandering in spite of this technique, there are two things you can consider:

Meditation. (I haven't tried it myself, but it is often mentioned on Personal Productivity SE.)
Some vigorous exercise before a study session or during a longer break. (See also How to quickly restore concentration?, which is actually about restoring concentration after an interruption, but the answers are more generally applicable.)

Make sure that you get enough sleep. In addition, you can also take a nap before a study session.
Some people find it helpful to visualize goals to maintain motivation. Alexander Heyne (on YouTube) proposes a different approach to goals; see his videos on goal setting & outcome goals versus habit tracking (and process goals): Why goal setting DOESN'T WORK (and what does) and Stop Setting Goals - Stack Your Habits. He does not talk about chess study, but his ideas should also work for this.
If concentration is still difficult in spite of all of the above, don't keep "banging your head against the wall". If you repeatedly force yourself to keep on studying in spite of being tired, you can create negative associations with studying chess.


Are there any papers that highlight the problems with rating systems?

It's a bit old, but this paper from 1995 by Mark Glickman (creator of the Glicko rating system) discusses some of the rating systems in use at the time, including the ones used by the USCF, FIDE, and the PCA. In it, several issues are mentioned, such as rating inflation/deflation, regional variations in ratings, variations in time controls, and the advantage of White. There's some other interesting stuff in there, like how natural ratings variation means that a stronger player will have a less than predicted actual performance against weaker players.

Not everything in it is still accurate. For example, at one point it states that the USCF rates events in the order they are received rather than the order in which they were played, but currently the USCF will re-rate the more recent event if an older event is submitted to it, so that is no longer a problem with that system. It also states that FIDE has a minimum rating of 2000, and that is no longer the case. The paper also obviously doesn't discuss any of the more recent systems. But it may be a good starting point.


What are some good resources one may use to get better at chess? (training etc)

I don't think this question is a duplicate, but I'm going to shamelessly reuse my answer to a related question anyway:

The internet is an amazing tool - for good or for ill. All of the following will help people at a wide variety of levels.

I'd suggest looking into some sort of tactics training. chess.com has a good reputation; I personally use lichess; I used to look at chesstempo. Practicing a few a day (or an hour or so a day) can give you an amazing boost; this is probably the best "bang for the buck". (I speak from experience!)

Find a good YouTube channel with a presenter who speaks to your level and has a teaching style you enjoy; there are a TON of options out there. Depending on your level, something like the Backyard Professor, IM John Bartholomew, any of the St. Louis Chess Club, MetoJelic, Dereque Kelley, etc. I enjoy all of those and many more (they're at widely different levels) for different reasons. (I enjoy others like the Ginger GM, too - but I definitely wouldn't watch him at a "lower" level... he'll give you bad habits that he can get away with.)

If you want to improve some openings, I can't stress chessable enough. My online rating jumped about 200 points just by going to this site every day for two months. (Yes, online ratings are "worthless": it's the relative level, not the absolute.)

Another option would be to find a player whose style you like or have empathy with, and go to chessgames to look through all of their games. Walk through them slowly, trying to figure out why they made the moves they did (when they did) - and why their opponent did what they did.

Beyond that, play games - and then analyze them afterwards. Even just walking back through slowly, trying to identify what went right or wrong (and what could have been better) can help a LOT. Lichess has the option to analyze your games for free - which is a HUGE boost. I've seen the advice "play slower games" (10+ min. on the clock) from quite a few people, as those games give you more time to calculate, analyze, and think. Practice visualization!

If you don't like the internet, there are always physical books - but I'll let someone with more experience on them weigh in. I've got some, I enjoy them, but I don't know enough to make recommendations.

Good luck!


Online defensive tactics training problems?

I enjoyed Andy Soltis' The Art of Defense in Chess.  It was all about finding hidden resources.

Remarkably, this book is available electronically for no cost, and legally I assume.  Here are a few links.

http://torrentz.eu/solt/Soltis%2C%20Andrew%20-%20The%20Art%20of%20Defense%20in%20Chess.pdf-3692550

http://ebookee.org/The-Art-of-Defense-in-Chess-by-Andrew-Soltis-1975-_1168031.html

Paper book:
http://www.amazon.com/The-Defense-Chess-Andrew-Soltis/dp/0679141081


How do I promote my pawn when the king blocks it?

This position is a draw with White to move. However, the same position would lead you to win if it was black to move (Zugzwang).

The basic theory for you to promote the pawn when the opponent king is having the opposition is you need to have your king in front of your pawn 2 ranks ahead of the pawn, (i.e. if pawn's on e3 King needs to be on e5) (opposition means - being right in front of the king when its his opponent's turn to move, for example- in your position black has gained the opposition with white to move), lets say in the same case, its black to move, that means white has the opposition and after black moves to lets say Ke8, e7 wins you the games as the king now has only 1 square to move that is Kd7, now as it is your turn to move, you play Kf7 and gain the opposition again in front of black king Kd7(sideways), so now black can't play Ke8 and you can promote the pawn and win the game.

In this game it's White to move and he gains opposition and put Black King in Zugzwang. (Make sure to read comments for the moves appearing in the box below each game)

[Date "????.??.??"]
[Result "*"]
[FEN "8/8/8/4k3/8/8/3KP3/8 w - - 0 1"]

1.Ke3 { Gaining opposition and putting Black king in zugzwang, so black king has to move and give up one of the key squares which is d4, e4 or f4. } ( 1.Kd3 {This is a blunder as now it will just be a draw } Kd5 2.e3 ( 2.e4+ Ke6 3.Kd4 Kd6 4.e5+ Ke7 ) 2...Ke5 3.e4 Ke6 4.Kd4 Kd6 5.e5+ Ke7 6.Kd5 Kd7 7.e6+ Ke8 8.Kd6 ( 8.Ke5 Ke7 9.Kf5 Ke8 10.Kf6 Kf8 11.Ke5 ( 11.Kf5 Ke8 12.Ke5 Ke7 ) 11...Ke7 ) 8...Kd8 9.e7+ Ke8 10.Ke6 ) 1...Kd5 { If Ke6, then white plays Ke4 and gains opposition again. } 2.Kf4 Ke6 ( 2...Kd6 3.Kf5 Kd5 4.e4+ Kd6 5.Kf6 Kd7 6.e5 Ke8 7.Ke6 ) 3.Ke4 Kf6 4.Kd5 Ke7 5.Ke5 Kd7 6.Kf6 Ke8 7.e4 Kf8 ( 7...Kd7 8.e5 Ke8 9.Ke6 Kf8 10.Kd7 ) 8.e5 Ke8 9.Ke6 Kd8 10.Kf7 Kd7 11.e6+ Kd8 12.e7+ Kd7
*

Here White King is only 1 rank ahead of the pawn and if black can gain the opposition, game will be a draw. It is Black To move and Black gains the opposition and draws.

[Date "????.??.??"]
[Result "*"]
[FEN "8/8/8/3k4/8/4K3/4P3/8 b - - 0 1"]

1...Ke5! { Now White has no way to gain back the opposition while being ahead of the pawn. } 2.Kf3 Kf5 3.e4+ Ke5 4.Ke3 Ke6 5.Kf4 Kf6 6.e5+ Ke7 ( 6...Ke6 { Also Playable } 7.Ke4 Ke7 { Both the same. } ) 7.Kf5 Kf7 8.e6+ Ke8 9.Kf6 Kf8 10.e7+ ( 10.Ke5 Ke7 ) 10...Ke8 11.Ke6
*

But if White is 2 ranks ahead of the pawn, then he can win the game even if black has the opposition as he has to give up the opposition soon as shown below.

[Date "????.??.??"]
[Result "*"]
[FEN "8/8/4k3/8/4K3/8/4P3/8 w - - 0 1"]

1.e3 { Now Black has to give up one of the key squares which is d5, e5 or f5. } 1...Kd6 2.Kf5 { And after this White wins as shown in above example. }
*


Why is castling through and out of check prohibited?

One rationale that I can think of for not allowing the king to move through check parallels that behind the possibility of capturing en passant after a pawn makes a two-square advance.

The typical pawn move is just a single square forward, and the possibility of advancing two squares on a pawn's first move was a relatively late addition to the game in historical terms. Since the "nature" of a pawn had long been to make a single square advance, when that new sort of pawn move came into being, the en passant capture was a natural counterpart: the pawn doesn't "jump" two squares ahead, but rather "marches" through the intermediate square, and an opposing pawn is thus allowed to capture en passant on the following move if it is in position to have captured the advancing pawn at the intermediate square.
With that explanation in mind, let's consider your rule. Like pawns, a king's typical, natural movement is only a single square in distance. And like the pawn's two-square advance, castling is a relatively new addition to the rules of chess that is intended to speed the game up. So just as the en passant capture reinforces the pawn's nature as a one-square mover, the rule prohibiting a king to castle through a checked square reinforces the king's nature as a one-square mover. He is thought of not as gliding over the checked square, but rather trudging through it. And just as an opponent's pawn has a chance to capture en passant, an opponent's piece guarding the intermediate castling square would be given the right to capture the king. Since that's not a legal part of chess, castling through check in the first place isn't either.

As for why castling is disallowed just because of the king being in check, I'm not so sure, but I'll speculate. If, in the analogy between chess and war, we think of a check to the king as a wounding attack, less severe than the lethal checkmate but damaging nonetheless, then it's reasonable to insist that the hobbled king can't make a swift, immediate escape via castling. But maybe that's just how I think of it.


What are the options to automatically identify games where the first move played was the best by a margin?

It is not too difficult to do this with a python script:
You basically start the engine as a subprocess and communicate via "uci".
I'll post some not very pretty code snippets and try to explain what you have to do:

engine=subprocess.Popen('./stockfish-5-        64',universal_newlines=True,stdin=subprocess.PIPE,stdout=subprocess.PIPE,)

def put(command):
    print command
    engine.stdin.write(command+'\n')

    if command!='quit':
        engine.stdin.write('isready\n')
        while(True):
            text=engine.stdout.readline().strip()
            print
            print text
            print
            if text == 'readyok':
                return

def get():
    engine.stdin.write('isready\n')
    while(True):
        text=engine.stdout.readline().strip()
        print text
        if text == 'readyok':
            break
        if text !='':
            print text

def getResult(depth):
    Result=[]
    while(True):
        text=engine.stdout.readline().strip()
        liste=text.split()
        if text[:22]=="info depth "+str(depth)+" seldepth" and liste[15]=='1':
            Result=[]
        if text[:22]=="info depth "+str(depth)+" seldepth":
            Result.append(text)

        if text[:8] == 'bestmove':
            break

    Scores=[]
    for line in Result:
        liste=line.split()
        Scores.append(liste[7])

    return Scores

def Game_Analysis(game):
    scorestring=''
    moves=''
    for x in range(len(game)-1):
        moves+=game[x]+' '
        command='position startpos moves '+moves
        put(command)
        get()
        put('go depth 15')
        Scores=getResult(15)
        for score in Scores:
            scorestring+=score+' '
        scorestring+='\n'
    return scorestring

get()
put('uci')
get()
put('setoption name MultiPV value 20')
get()

print Game_Analysis(game)

put('stop')
put('quit')

So, get() and put() are for communicating with the engine.

put('uci') starts the dialog.

put('setoption name MultiPV value 20') tells the engine to return the best twenty moves. (In your case you really only need 2)

command='position startpos moves '+moves
put(command)  This sets up the position, unfortunately the moves aren't pgn but in uci-format. So you'll probably have to transcribe or use FEN.

In GetResult() I extract the 20 best scores of the position. Then you only need to look for a big difference between move one and move two.

Game_Analysis(game) extracts the 20 best scores for every position in a game, here given as a list of uci-formated moves.

To deal with the uci-format and really understand these commands you should have a look at the uci=Universal Chess Interface.


Should you state your rating if you want to play in a simul?

First off, Kasparov is not a big fan of losing.  That's an important detail.  I wont weigh in too much on his personality, but if you look at the comments on that video, there are quite a few strong opinions about what kind of person he is.

I don't know what the rules were for that simul, but if they were the same as the Kasparov's current website:

  Players must be true amateurs who have 1999 ELO points or less, no exceptions. No player who has ever held a Rating of 2000 or over is permitted--it is contrary to the spirit of the simul and to the agreement. No coaching or computer assistance is permitted.

So if the organizers in Johannesburg were operating under these rules, then indeed they were out of line.

If you watch the whole thing, it looks like the under 2000 rule may not have been in place back then, but he did specifically ask the coordinators to tell him who the strongest player was.  It appears they did not take into account a coach helping these players during the simul, and so they pointed elsewhere.

In some sense, it does make sense.  At the GM level, you are always playing to your opponent.  You have to know something about them.  He was playing on assumptions about the capabilities of his opponent, and those assumptions turned out to be false.

On the other hand, you are right about this event being something that's supposed to be fun.  I know I generally agree with it, but not everyone does.  Kasparov does seem to care that a player can walk away claiming "I beat Kasparov" when Kasparov was not playing his best at the time.  Instead, he was playing a version of Kasparov designed to do "something else," whether that's saving time for other boards or trying to teach the amateurs something about chess.  We don't know what his purpose for being at the event was, but we do know he values his name and he values his record.


Is there a formula that converts a number from 0 to 959 to a corresponding chess960 position?

From Wikipedia:

  White's Chess960 starting array can be derived from its number N (0
  ... 959) as follows:

  a) Divide N by 4, yielding quotient N2 and remainder B1. Place a
  Bishop upon the bright square corresponding to B1 (0=b, 1=d, 2=f,
  3=h).

  b) Divide N2 by 4 again, yielding quotient N3 and remainder B2. Place
  a second Bishop upon the dark square corresponding to B2 (0=a, 1=c,
  2=e, 3=g).

  c) Divide N3 by 6, yielding quotient N4 and remainder Q. Place the
  Queen according to Q, where 0 is the first free square starting from
  a, 1 is the second, etc.

  d) N4 will be a single digit, 0 ... 9. Place the Knights according to
  its value by consulting the following table:

0     N   N   -   -   -
1     N   -   N   -   -
2     N   -   -   N   -
3     N   -   -   -   N
4     -   N   N   -   -
5     -   N   -   N   -
6     -   N   -   -   N
7     -   -   N   N   -
8     -   -   N   -   N
9     -   -   -   N   N

  e) There are three blank squares remaining; place a Rook in each of
  the outer two and the King in the middle one.


Do any grandmasters win more with black than white?

The short answer
Yes, they do, although very few GMs do and by a margin of less than 10%. This does not seem to be due only to random factors (see long answer).

An example is GM Joseph Gallagher. As you can see in his FIDE profile page, he has the following games record (as for 15 Dec. 2020):
White +124 =118 -73, score = 58.1%
Black +126 =124 -67, score = 59.3%

The long answer
To obtain the figure above I used the games published by TWIC, issues 920-1358 (25 Jun. 2012 to 16 Nov. 2020). I selected games where at least one of the players was a GM. And I kept only players with more than 50 games per color in the dataset. This ensures that scores are calculated with a 90% confidence interval of at least ±2%, and, since players in the dataset have in average a couple of hundred games, scores are usually still more accurate. The resulting dataset had 561K games for 1168 GM players.
In this case, the average scores where 65.5% for white and 56.9% for black. This is higher than in the databases you mention because being a GM most other players have a lower rating and they're more likely to win. (If I took only the games where both players were GMs, the average scores were 52.9% for white and 43.3% for black.)
As shown in the figure above, the average difference of scores between both colors is 8.6%, favorable to white. Still, there were 38 players who had better results overall with black. The five players with the highest difference in performance favorable to black in the dataset were:
                    WhiteScore  BlackScore  Difference
Bryan Smith            55.2        62.9        7.8
Essam El Gindy         52.0        58.8        6.9
Jean-Luc Chabanon      50.5        57.2        6.7
Justin Tan             54.5        61.2        6.7
Mihai Suba             57.9        63.8        5.9

I would like to bring your attention to one of these players, Mihai Suba, who is known for his book Dynamic Chess Strategy. In it he disagrees with white's first move advantage theory.
Note: If you look at these players' FIDE profile pages, you might find some discrepancies, due to the different characteristics of both datasets. The FIDE data includes all FIDE rated games (whether the player was already a GM or not); while my dataset contains games published on TWIC (FIDE rated or not) from 2012 to 2020 only if the player was already a GM.
But is it a correct answer?
Now, just because of randomness we would expect that some players had better results with black than with white. But is it the case? Do those players really perform better with black pieces or is it simply a random illusion? To check this I plotted the evolution of the score difference as the number of games increases for several players.

As you can see, the score difference varies widely when there are few games. But as the number of games increases, the variability decreases. In some cases, the score difference remains consistently above 0. In other cases, it occasionally crosses the line.
So, yes, there are some cases that cannot be considered a statistical artifact.
And what about differences in style?
You didn't really ask about it, but since you mentioned it in your question I had a look at it. For this I divided the players in three groups according to their score difference:

Upper 5%: Mostly players with better results with black
Lower 5%: Players with much better results with white
Those in the middle

And then I looked which kinds of openings they used, classified according to the five main ECO categories:

A: Flank openings
B: Semi-Open Games other than the French Defense
C: Open Games and the French Defense
D: Closed Games and Semi-Closed Games
E: Indian Defenses

It would seem that GMs who have better results with black pieces tend to use openings of the groups A and B more often than the other players, and the other groups less often. Although more detailed analyses would be necessary to arrive at more solid conclusions, this can give you some food for thought.

Update 19/02/2020
Dataset and script
Following the request by @stevec, I have shared the dataset and script used to write this answer on github.
It can be used to investigate some of the proposals made by other users (@HaukeReddmann, @SecretAgentMan) in the comments.
Further tests
@Grade'Eh'Bacon, suggested in a comment comparing the observed distribution of the difference in scores to the expected distribution under only random influences. I had already done this analysis, but I decided not to include it because the answer was rather long. But since it has been requested, I share it here.
If the distribution shown in the score differences plot at the top of the answer was due only to random factors, we would expect a normal distribution (aka Gaussian distribution, bell curve). This is the hypothesis assumed in Elo calculations and can be checked with a Monte Carlo simulation.
One way to test if a variable follows a normal distribution is with a Q-Q plot (see below). If the observed score difference followed a normal distribution, the points would be close to the diagonal line. This happens in the middle zone, but not in the extremes. We have a distribution with heavy tails, that is, there are too many players with better results with black and too many players with much better results with white to be due to random causes alone.

The results of the Shapiro-Wilks test, which is also used to test for normality is also consistent with the hypothesis that the distribution is not normal. This supports the hypothesis that there is something else going on apart from randomness.
And I also repeated the analysis with another independent dataset of games from the ICCF. And I obtained comparable results.


WDL gives win/draw/loss for a position
DTZ gives distance to zero for the 50-moves draw rule

Both files are needed, absolutely. Chess engines assume both files are there, and would only check one of those at run time. It's your responsibility to make sure you have both files. There's a good opportunity your engine will crash if you don't.

You're giving yourself trouble if you leave out one. Download them both or do nothing.


What is the highest value of pieces on this particular 6x6 board, without any of them attacking each other?

This was the correct answer with 100 points!


Because if black takes on c4 it loses Control of the centre and white will generally get that c pawn back sooner or later


How to send uci messages from c# app to stockfish on android?

When you're using C#, you can use any UCI engine in the same manner.  With C# you have to add an event handler to the OutputDataReceived event (and optionally the ErrorDataReceived event).  As a quick example:

ProcessStartInfo si = new ProcessStartInfo() {
    FileName = uciPath,
    UseShellExecute = false,
    CreateNoWindow = true,
    RedirectStandardError = true,
    RedirectStandardInput = true,
    RedirectStandardOutput = true
};

myProcess = new Process();
myProcess.StartInfo = si;
try {
    // throws an exception on win98
    myProcess.PriorityClass = ProcessPriorityClass.BelowNormal;
} catch { }

myProcess.OutputDataReceived += new DataReceivedEventHandler(myProcess_OutputDataReceived);

myProcess.Start();
myProcess.BeginErrorReadLine();
myProcess.BeginOutputReadLine();

SendLine("uci");
SendLine("isready");
SendLine("ucinewgame");

And the methods alluded to above:

    private void SendLine(string command) {
        myProcess.StandardInput.WriteLine(command);
        myProcess.StandardInput.Flush();
    }

    private void myProcess_OutputDataReceived(object sender, DataReceivedEventArgs e) {
        string text = e.Data;
        //Debug.WriteLine("[UCI] " + text);
    }

This is an incredibly simplified example.  In my own code I have a semaphore in order to fully process each output line before moving on to the next one and several semaphores in the UCI start and "isready" handling.

For a full overview of the UCI protocol, check out the specification.


Can it be said that draws occur less often between top-level players of equal caliber, rather than machine draws?

The draws among chess-playing machines tend to be far more than players of 2700-plus Elo Level. Of 100 games, and I mean in 100 matches, machines will have 60-70 draws compared to humans where they may have 50 draws.

Now the score can fluctuate a lot from the players side owing to different conditions .

Both players are not in a Spirit/mood for fighting as like Kasparov/Karpov 1985 WCC.
Unlike a computer, a strong 2800 player may not be in his best form. He may have different reasons like health/family problems, or other factors which may cause a setback .
A Player may even make a basic tactical mistake and lose the game like Anand did against Carlsen in 2014 WCC match.

These are some reasons that a machine does not encounter at all, and plays freely. You can even check the database among players, and if possible there is a lot fo history associated with famous chess games. You could find many interesting stories which would adjudge many of the reasons above and even attract various other info.


Nice one:

 1 Kf6 Ra8! 2 Kg7 Bb8 3 Kh8 Be5#!  ("Indian theme")


A Discovered Check is a "discovered" attack against a King--when a pawn or piece moves aside, to reveal a check by another piece. It's a powerful weapon, because check is given by a piece that does not have to move--and therefore, the piece that does move is free to make other threats, or even captures.

To a certain extent, you will naturally begin to see opportunities for discovered checks as you play more, because they, like all discovered attacks, are all about lines of influence. Tactics practice--all tactics, not just discovered check tactics--will help you begin to visualize these without searching for them specifically. A google search for "chess tactics" produces a decent selection of online tactics trainers.

To look for discovered checks in particular, look for pieces that would be checking the opponent's King, if not for one of your own pieces blocking the way. For example, in the diagram below:

[FEN "r2q1rk1/pp1n1ppp/3p4/2b1p3/3nPPQ1/2NB4/PPP3PP/R1B2RK1 b - - 0 1"]

Black to move.

Black's Bishop on c5 would be checking White's King, if not for the Black Knight on d4. If Black's Knight moves, it will reveal a discovered check. In fact, Black has an opportunity to win material here:

[FEN "r2q1rk1/pp1n1ppp/3p4/2b1p3/3nPPQ1/2NB4/PPP3PP/R1B2RK1 b - - 0 1"]

1...Nxc2+! 2.Kh1 Nxa1

Even though the pawn on c2 is defended by White's Bishop, the Black Knight may take it with impunity, because White must respond to the discovered check. Then Black is free to win a further exchange, Knight for Rook, after White's King runs away.

Pawns can reveal a discovered check as well, and they're sometimes much more dangerous than pieces, since they can effectively threaten anything, and even advancing at all can make them powerful weapons.

In the situation below, material is equal and there's a lot of tension on the board, but White has a devastating discovery that wins instantly...

[FEN "1k4rr/pp1n1pq1/2b2p2/2p1P3/5Q1p/2N2N2/PP3PPP/3R1RK1 w - - 0 0"]

1.exf6+!

White's pawn will take the Black Queen next turn, with no real repercussions, and he should go on to win with ease (if Black doesn't simply resign on the spot!).

One common pattern is often called a "windmill": where one piece takes advantage of a trapped King by repeatedly alternating between giving check and discovering another check. The position is from a somewhat famous game by a 13-year-old player you might have heard of:

[White "Donald Byrne"]
[Black "Bobby Fischer"]
[FEN "r3r1k1/pp3pbp/1Bp3p1/8/2bP4/Q1n2N2/P4PPP/3R1K1R w - - 0 0"]

1.Kg1 Ne2+ 2.Kf1 Nxd4+ 3.Kg1 Ne2+ 4.Kf1 Nc3+ 5.Kg1 axb6

By the end of the windmill, Black has already gained a Bishop and a pawn, and he will soon pick up the Rook on d1 as well, and go on to win handily.

A common thread in discovered check tactics is long, open lines directed at the enemy King. Because discovered checks are generally delivered from a medium or long distance, an open board and few pawns around the King make them easier to engineer. Look for pieces that could deliver check, if only some other piece or pawn was removed.

If you find a discovered check, look at all the places that the discovering piece could move: can you take free material? Make other threats that your opponent can't answer? Use a windmill to pick up many different objectives? Discovered checks are one of the most versatile threats in the game--when you get used to seeing them, your tactical levels will improve dramatically.


Systematic approach to learning opening/endgame theory?

I will preface this by saying that I'm a 2150 USCF player who has had the same issues that you are struggling with in the past. What I'm about to tell you comes straight from my own experiences playing chess all these years.

Don't study or memorize any theory straight up. I find it difficult to retain information like that and the potential for it to be used is minimal. The best way to learn theory is to first forget about it, and instead play games with that opening. Then after the game, when you are at home look up the theory for whatever variation you are playing and learn the theory AFTER you've played a tournament game with it. This usually consists of finding books related to the opening you've played, poring quickly through some GM games in the same line, and annotating the game you just played.

The amount of theory you need to know is enough that you
1) won't fall into any opening traps and
2) that you have a general sense of how to play your position once you are out of book.

There isn't a set number of moves you need to memorize, but these two criteria are questions you should ask yourself if you think the amount of theory you know in the opening is insufficient.

You might say that you are scared that if you don't know the theory, you might lose straight out of the opening. From my experience, you will win if you are the better player no matter what opening you play, and you will lose if you are the worse player even if you are armed with loads of theory. You say yourself that you feel that these other players outplay you out of the opening, but honestly, I have a feeling that they would've outplayed you no matter what the opening choice. Upping your entire game, and analyzing what you could have done better in the resultant opening and middlegame positions is far more important than a few temporary setbacks in tournament play.


How should I make a 6 year old think more?

What else can I do to make her understand this

Wait a few years. A 6 year-old's mental capacity is very limited. The good news is that at that age and for several years to come her mental capability is increasing rapidly.

Trying to teach a 6 year old the same way you teach a 12 year old is stupid whether it is maths you are teaching or chess. At 6 the emphasis should be on enjoyment if you still want her to be playing chess at 12.


How do you keep chess fun when your opponent constantly beats you?

There are many people who want to play chess with you. You can play chess online! Online sites such as chess.com and lichess.org will match you with opponents of similar rating so you should win about 50 percent of the time. Furthermore, playing online as well as studying chess will immensely improve your chess, and maybe you'll play your friend again and this time you will win!


A book often recommended to beginners is Logical Chess: Move by Move by Irving Chernev. It contains 33 games with text explanations for every single move.

Dan Heisman also recommends other books in his web site, here are a few:

Chess: The Art of Logical Thinking - Neil McDonald
A First Book of Morphy by del Rosario
Most Instructive Games of Chess Ever Played - Irving Chernev
Chess Master vs. Chess Amateur - Euwe and Meiden

[edit] Here's a PGN file of Logical Chess that you can play through using a game viewer like Scid vs. PC while you read the book. Or you can just use a regular chess set.


Which late starters have been able to become grandmasters?

Oscar Shapiro was the oldest player to become a master. He did it at the age of 74.
Wilhelm Steinitz was the oldest world chess champion. He won the title from Zuckertort in 1886 at the age of 50 and held it until he was defeated by Lasker in 1894 at the age of 58 years and 10 days.

Source


White can do nothing right now, because he made the last move (Ne1). Black can simply sacrifice the exchange on f3, keeping the pin intact, and aim the other rook at f3. Then, White's position will collapse entirely.

There's no way White can escape the pin, e.g. after h4, Black can just ignore the attacked bishop:

[FEN "1r4k1/2p2pp1/5r1p/p1p1p1bq/P1PpP1b1/1P1P1NP1/4QPKP/1R1RN3 b - - 0 1"]

1... Rxf3 2. Nxf3 Rb6 3. h4 Rf6 4. hxg5 Bxf3+


Will going to more chess tournaments and playing the Open section make me stronger and more experienced chess player?

No. Playing against those who can easily defeat you will not make you stronger. And it will hose the Open section, too, as you are effectively a "bye". If am referring to tournaments where there is a vigorous Open section, of course. When I played in the NY State championship, the Open section was all 2200+ and included IMs and GMs.

There are a few threads here on how players can improve. Search for them.

In a nut shell:

Work tactical exercises
Attend your local chess club and

a. play in your section

b. ask better players (+400 rating over yours, if possible) for help with analysis, and
Find an instructor to help you with specific weak points.
Once you are established at the chess club, you and an opponent can play a rated match. That is, you and your opponent can play a rated best-of-5 match or whatever. Choose an opponent who is 100 or maybe 200 points over you for a real challenge. You'll need your club's TD's approval.


Does chess.com analysis board use my own CPU?

Yes, it does. It uses stockfish.js, the Javascript port of Stockfish, which can run on web browsers. You can see stockfish.js mentioned somewhere on the chess.com analysis board. Also, I can tell that the computer fan starts working harder when I run an analysis, and looking at the "top" command shows that the web browser is using 100% CPU.


I'm looking for more information on "Goldmann" of the Goldmann Variation (Caro-Kann)

Warren H. Goldman wrote a book titled "New Ideas in Old Settings: Q-B3 against the Caro-Kann". It was published by Chess Ltd. (December 1979). It's still available from Amazon, and perhaps other sellers.

In Kaissiber No. 15 (Summer 2000), there was a thirty-page article about the "Dispute of Theoreticians" on the Goldman Variation (1.e4 c6 2.Nc3 d5 3.Qf3) and its exponents.


Estimating probability of player playing move in the opening

Intuitively we should look at the player's games for early moves and book moves for later. This is because as we get further in a game, the number of possibilities increases, therefore the sample size of player games decreases. In this scheme, we are assuming that the player in question behaves as the average player does in the long run given the positions they usually seek from the opening.

You could use a rule of using the player's games if there are more than 5 to use, and using other players games otherwise.


No. The problem is that the queen covers too many squares.

Consider this (illegal) checkmate position with king and 2 knights vs king and queen:

[fen "kq6/2N5/KN6/8/8/8/8/8 w - - 0 1"]

If you remove either knight then the queen can take the other one.


In improvisational music, like jazz for example, the musicians will play a song that has been composed in advance, but by choice they go "off-script" and, cooperatively, make their very own creation in the moment, guided by the structure of the composition but nevertheless doing something distinctly new with each performance. In order to do this well, and create something of beauty that actually sounds good, jazzers need to have a solid understanding of how and what to play; in a word, they need to know what moves make sense, among the essentially infinite possibilities that are available to them, within the musical context that they're in. Far from being "mere" players of the music, they are composing on the spot.

Something similar - though different in important ways - happens when two players sit down to play a game of chess. The most notable difference of course is that here, unlike the musical setting, the play is competitive rather than cooperative. That is why there comes a point in every chess game where one is forced to improvise. You can try coming in with a pre-composed script that you want to play, but your opponent most likely isn't going to play along. Each player will have to compose his or her half of the game on the spot.

You can think of a chess opening that has its own name and well-known variations much like a good song with its musical score. Through much playing, it has stood the test of time (both on the White side and the Black side) and is recognized as something of worth. In this sense, such openings are a good thing for a chess player to become familiar with. (Consider this: would you rather listen to music made by someone who's already absorbed a lot of other music, or someone who's never heard any before?) But just as someone who has done nothing but memorize the scores of a few good songs would be at a loss if asked to compose a great new piece, a chess player who has focused too much on memorizing opening lines will continually run into points where he's at a total loss as to what to do.

In each case - the composer and the chess player - what is truly useful for future performance is to seek an understanding as to what makes the individual components of a song/opening good or bad, and how they fit together to work toward a common goal, be it an aesthetically pleasing piece of music or a won game of chess. To make one's own worthwhile creations, it is more important to know how to find one's own way than just to know what others have done in the past. But the latter kind of knowledge can definitely help with the former, as long as one focuses on the ideas and principles underlying the moves, rather than just the moves themselves.

As an addendum, here is an illustrative example of how not to use book knowledge in one's games. During a 1988 tournament, a strong GM was about to have a game as Black, and was skimming through the latest Informant for some up-to-date theoretical information. There he found a game in the Petroff Defense, in which Black managed to secure a draw, that featured what was listed as a theoretical novelty (TN) on move 5 for Black. Without thinking much about the value of the move, our intrepid GM decided to give it a go himself. The game played out so:

[FEN ""]
[White "Alonso Zapata"]
[Black "???"]
[Result "1-0"]

1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. Nc3 Bf5 6. Qe2 1-0

Black is going to lose a piece, so he decided to resign. What had gone wrong? Well, the game that had slipped into the Informant had in fact been a pre-arranged draw between GMs Tony Miles and Larry Christiansen, in which they each mindlessly played out some moves and shook hands:

[FEN ""]
[White "Anthony Miles"]
[Black "Larry Christiansen"]
[Result "1/2-1/2"]

1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.Nc3 Bf5 6.Nxe4 Bxe4 7.d3 Bg6
8.Bg5 Be7 9.Bxe7 Qxe7+ 10.Be2 Nc6 11.O-O O-O 12.Re1 Rae8 13.Qd2 Ne5
14.d4 Nxf3+ 15.Bxf3 Qd7 16.c3 b6 17.Rxe8 Rxe8 18.Re1 Rxe1+ 19.Qxe1 Kf8
20.g3 ½–½

If our strong GM had spent even a few moments thinking about the why of the "script" he'd just glanced at, he never would have played as bad a move as 5. ... Bf5??. Note too how important it was for White to be ready to improvise; Black's fifth move is so bad that White couldn't have expected it to be played, but when it was, White rightly sensed that something was off about it, and duly found the appropriate punishment. The moral of the story: even the strongest of players need to be careful not to rely too much on book "knowledge." It all ended well for our hero though, as he now enjoys the title of world champion.

Zapata - Anand (Biel 1988)


Are there any grandmasters who always play until checkmate?

To become Grandmaster, you must win many tournament games. They take many hours, sometimes multiple games per day, or many days in a row. Tournaments are exhausting. If you are tired then you make mistakes, and making mistakes means you don't play at the required level to become Grandmaster.

Players who always waste a lot of time by playing on until checkmate instead of resting aren't very likely to become Grandmaster.


I think you are making good use of your coach from the sound of it.  Perhaps you are not studying the correct books for your rating.  And you should be heavy on puzzles and basic endgames; if your coach hasn't pushed you toward that there may be reason for concern.


How does Stockfish ensure an incremental change made is beneficial?

Disclaimer: not an expert.

As I understand the so-called "Fishtesting", you write a patch and submit it to the queue. The system then plays your patch against the previous engine at short time controls. Very many games are played (this is why computing power is needed to improve your engine). If the patch proves to be stronger at short time controls, another test is performed and longer time controls, and if the patch passes again then it's promoted to become the main version.

Example: this patch. You can see the user submitting the patch is "protonspring", and he was trying to simplify the passed pawns code. Fishtesting played the new patch against the old version 5451 times, with a result of 20.1% wins, 23.3% losses, and 56.5% draws. The new patch is inferior, so it's rejected. As you can see from the Fishtest main page, most patches fail.


There are a lot of titled players with high functioning autism.

One known is GM David Navara, but there are others. It is discussed if Bobby Fischer was Asperger too. There was a buzzing Magnus Carlsen was autistic too, but looks false according to Quora. Another example of GM that looks to be autistic is GM Julio Granda from Peru.

As for Down Syndrome, they have not the abilities an Asperger has, but they can learn how to play chess competitively.

Subramaniam Karaan, from India, has Down Syndrome, and he is rated 1806 when I write on FIDE list. He is also rated 1832 in blitz, and was close to reach 2000 in 2015.


Yes this seems to be a drawn endgame, most variations actually end up in a queen vs queen+knight situation which is generally a drawn endgame (one example below). But that doesn't mean the puzzle is flawed because as far as I know chesstempo puzzles are just about finding the best moves a priori, thus not always about a winning line. Good tactics trainers (such as chesstempo, lichess...) usually only say which side is to move, and the objective of the puzzle is actually part of the puzzle itself (that is, whether one is to play to mate, play to win material, or play to draw etc.)

In this particular position black has to come up with the best moves in order to hold the game it seems.

 [title "One possible continuation, 1/2-1/2"]
 [fen "8/8/1p6/p1p3p1/P1P1B1K1/1P2kP2/5n2/8 w - - 0 1"]

 1. Kf5 g4 2. fxg4 Nxe4 3. Ke5 Kd3 4. Kd5 Ng5 5. Kc6 Kc3 6. Kxb6 Kb4 7. Kc6 Nf7 8. Kb6 Ng5 9. Kc6 Kxb3 10. Kxc5 Kxa4 11. Kd6 Kb4 12. c5 Ne4+ 13. Ke5 Nxc5 14. g5 a4 15. g6 a3 16. g7 a2 17. g8=Q a1=Q+ 18. Kf5 Qf1+ 19. Kg6 Qg2+ 20. Kh7


Black repertoire for players who love the English Opening

The reality is that you cannot force such openings as black, but you can pick openings that may suit your style.

I really think that the Nimzo-Indian/Queens-Indian may suit your style very well. They will not get you queenless positions too often right out of the opening, but the nature of the Nc3 in the Nimzo, and it often getting exchanged resulting in doubled pawns for white, you will get a lot of strategically complex positions that have structural weaknesses to work against (usually in exchange for the bishop pair), and there is often a lot of maneuvering. In the Queens-Indian, you get the fianchettoed bishop you like, and nice control over e4, which allows you to try and chip away as the white center. I have also gotten a number of nice kingside attacks too against the white Kg1.

This has been my bread and butter opening pair as black against 1.d4 for decades, and I like the type of positions that you like. The theory is old now, but if you can get a hold of the book "Understanding the Queens Indian Defense" on eBay, it does a great job of teaching the underlying ideas. You can also study Karpov's games, as this was his main weapon as black during his peak years.

In the Nimzo take this famous game in the Huebner variation of the Nimzo. Of course, there are many variations, and you would have to learn more than just the Huebner.

 [Event "World-ch27 Fischer-Spassky +7-3=11"]
 [Site "Reykjavik"]
 [Date "1972.07.20"]
 [Round "5"]
 [White "Spassky, Boris Vasilievich"]
 [Black "Fischer, Robert James"]
 [Result "0-1"]
 [ECO "E41"]
 [BlackElo "2785"]
 [PlyCount "54"]
 [EventDate "1972.07.11"]
 [EventType "match"]
 [EventRounds "21"]
 [EventCountry "ISL"]
 [FEN ""]

 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. e3 Nc6 6. Bd3 Bxc3+ 7. bxc3 d6 8. e4 e5 9. d5 Ne7 10. Nh4 h6 11. f4 Ng6 12. Nxg6 fxg6 13. fxe5 dxe5 14. Be3 b6 15. O-O O-O 16. a4 a5 17. Rb1 Bd7 18. Rb2 Rb8 19. Rbf2 Qe7 20. Bc2 g5 21. Bd2 Qe8 22. Be1 Qg6 23. Qd3 Nh5 24. Rxf8+ Rxf8 25. Rxf8+ Kxf8 26. Bd1 Nf4 27. Qc2 Bxa4 0-1


How to defend from the crazy knight attack opening at Nf3 ..., Nd4 in Atomic chess?

Black, who defends, should move its Knight to h6. There it protects f5 so if white moves its knight there, black can capture it. Additionally, if white does Kb5 with the intention to attack Black's Queen (and potentially king, if black attempts to defend the queen), Black can go forward (Ng4) and then Black wins: Black can either capture a pawn next to the king, or the queen if White moves this pawn, and white can capture the queen with some other pieces when black does Ng4, but black's king is still safe.

[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. Nb5 Ng4 (3. Nf5 Nxf5) 4. f3 Nf2 5. Nxc7 Nxd1# 0-1

It can happen that white does h3 after Nh6 to block a potential Ng4 from black, and then black has to move a pawn to protect his pieces if white would move Nb5:

[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. h3 c6


Where can I find lists of best games per tournament?

Chess Informant quarterly subscription gives you the best of games played in that quarter.

Or, The Week In Chess is the raw scores of games with no commentary and no qualifications.


How good is this variant of the Sicilian defense?

I would actually call this a trap that loses black his ability to
  castle.

I would call it a double blunder, first by white with 5. Bc4 then by black with 5. ... Nxe4.

  Is there a name for this?

It is unusual for blunders to be given names although it does happen in special cases. This isn't special.

  Is there any counter to this variation?

... Qa5+ is the obvious one after which white looks to be in a lot of trouble to me.

Deliberately playing bad moves in the hope that your opponent will blunder is called "hope chess". If you want to improve then you have to try and stop doing that because it won't work against good players.


If your question is "Do I have to tell my opponent that he just made a move from where checkmate is forced?", the answer is "No", you don't have to tell your opponent he is setting himself up for checkmate. In fact, that is rather the point of the game!

The only times you have to tell anything to your opponent is:

When offering a draw
When you want to adjust a piece.

If your question is "Do I have to tell my opponent that he is in checkmate?", the answer is still technically "No". Even the customary "Check" and "Checkmate" are optional.

Practically, if your opponent does not grasp that he is in checkmate it may be useful to point that out to him one way or another, and the traditional "Checkmate!" should do the trick.


Touch a piece and then claim opponent's previous move was illegal

In standard play (each player has at least 60 minutes for all the moves) it makes no difference when the illegal moves is spotted the position must be restored to the one before the illegal move even if that was several moves ago.

In rapid or blitz Appendix A4 part 2b applies:

  b. An illegal move is completed once the player has pressed his clock.
  If the arbiter observes this he shall declare the game lost by the
  player, provided the opponent has not made his next move. If the
  arbiter does not intervene, the opponent is entitled to claim a win,
  provided the opponent has not made his next move.

Provided white has not released the bishop on a different square the claim for an illegal move stands and white wins the game.

EDIT: As of 1st January 2018 the rules for rapid and blitz have been brought into line with standard rate. In all 3 cases there is a time penalty for the first illegal move (1 minute for blitz and rapid, 2 minutes for standard) and only the second illegal move loses you the game.


Alekhine's Defense variation, understanding white's overextended pawns, black's multiple early knight moves

In short, white may well be overextending.

From black's point of view¹, white is offering many targets for black to attack :

d4 as c3 is not possible anymore, and if e5 is traded for d6.
e5 if d6 gets traded for d4
c4 if white's king bishop moves anywhere useful
Behind the pawns is a lovely place to land knights (d3 via b4 is not uncommon, e3 via f5 seldom happens…)

Once white's pawns are fixed, one can wonder about what advancing them actually achieved : white loses as much time pushing pawns as black moving the knight.

¹ which I adopt as an all-time Alekhine Defense player myself.


If White tries to hinder your plan by exchanging the bishops he loses the pawn endgame. I have provided brief analysis in the below diagram, see the sublines. Then I have tried to play this endgame with both colors versus computer.

Computer chose 1...Kf8 as strongest but with some "only moves" I managed to save the draw. This is illustrated in the below diagram as the main line.

I played your plan with ...g5 + ...Kh7 but computer found good resource in Be8!, which secures a draw. You will find my play as Black in the below diagram as a subline.

To conclude: you can not exploit your advantage because White generates enough counterplay thanks to your kingside pawns being on the color of your bishop.

[StartFlipped "0"]
[Title "Black to move"]
[fen "6k1/p4p2/1p2pPp1/7p/3Pb2P/1B2P1P1/P7/2K5 b - - 0 33"]

1...Kf8 (1... g5 2. hxg5 Kh7 3. Ba4! (3.Bc2? Bxc2-+ 4.Kxc2 Kg6 5.e4 Kxg5 6.e5 Kf5 7.Kd3 $8 b5 $22 8.a3 a5 9.Ke3 b4 10.axb4 axb4 11.Kd3 b3 $8 12.Kc3 Ke4!-+) 3...Kg6 4. Be8!= $8 Bf3 5. Kd2 Kxg5 6. Bxf7 Kxf6 7. Be8 Kg5 8. Bd7 Bd5 9. a3 Kg4 10. e4! Bxe4 11. Bxe6+ Kxg3 12. d5 h4 13. d6 Bc6 14. d7 Bxd7 15. Bxd7 h3 16. Bxh3 Kxh3=) 2.Ba4! a6 3. Bd7! Kg8 4. Be8! Kf8 5. Bd7 Kg8 6. Be8 Kf8 7. Bd7 Kg8 1/2-1/2


Is there a difference between +W -L =D and +W =D -L?

The only difference is the sequence they are written down.
Some like WLD so you can easily see the difference in scores.
Some like WDL as that goes from best to worst in sequence, but makes it harder to compute the difference at a glance.
Compare to TV channels showing football scores.
some have score1 team1  score2 team 2
others have team 1 score1  score2  team 2
some might even have score1 team1 team2 score2
clearly the middle one is easiest to see at a glance how the game score is without having to search and ensure you matched the right score to each team.  You know who is playing and all you need is the two scores and which one belongs to one team.  The middle one does that best.
It is just preference. And PHBs are not good at considering things like ease of use or other significant factors.


I don't have Rybka 4 but I do have the free version (Rybka 2.3.2). Rybka 2.3.2 doesn't support engine book. To verify this, open the engine in command, then type "uci". Look at how I did it.

Look the UCI options, we have one for multi-pv and others. But there is nothing for an opening book. If the engine doesn't support an opening book, you have to rely on a GUI to do it, for example, Fritz.

On the other hand, if you do the same thing to Stockfish, you'll see a Book options where you can specify path to your book be used by the engine.


Let's forget for a moment that it's a Najdorf.

You were cramped because you never gave yourself space. Instead, you spent a lot of time wandering around with your knight and bishop and opening lines against your own king. You didn't develop. You didn't counter-attack.

When White castled on the opposite side to you, they were making a simple declaration: I will checkmate you unless you checkmate me first.  This is absolutely typical in the Najdorf and it requires Black to carefully balance counter-attack and defence. Attacking on the queenside usually requires ...b5 (kicking the bishop with tempo), ...b4 (kicking the knight with tempo) and ...Rc8 (aiming at the king).

There's a good lecture by Jonathan Schrantz at the St Louis Chess Club that covers a lot of the Najdorf-specific ideas. ...b5 and ...d5 are the big breaks that you need to try to get in.


What are the official rules if your opponent makes an illegal move?

By the FIDE Laws of Chess, article 7.4:

7.4

a. If during a game it is found that an illegal move, including
failing to meet the requirements of the promotion of a pawn or
capturing the opponent’s king, has been completed, the position
immediately before the irregularity shall be reinstated. If the
position immediately before the irregularity cannot be determined the
game shall continue from the last identifiable position prior to the
irregularity. The clocks shall be adjusted according to Article 6.13.
The Articles 4.3 and 4.6 apply to the move replacing the illegal
move. The game shall then continue from this re-instated position.

b. After the action taken under Article 7.4.a, for the first two
illegal moves by a player the arbiter shall give two minutes extra
time to his opponent in each instance; for a third illegal move by
the same player, the arbiter shall declare the game lost by this
player. However, the game is drawn if the position is such that the
opponent cannot checkmate the player’s king by any possible series of
legal moves.

That is, on the two first illegal moves of your opponent, you gain time on your clock (two minutes, which likely does nothing), but on the third illegal move of your opponent, they lose the game (unless it was already impossible for them to lose it).


Are there brute force engines which examine all possible moves to each depth?

The answer is yes and no.

http://www.gamedev.net/page/resources/_/technical/artificial-intelligence/chess-programming-part-iv-basic-search-r1171
Has a pretty good explanation on how chess engine works.

In Chess, for example, a typical branching factor in the middle game would be about 35 moves. That is, after every move, there will be around 35 possible valid moves.

Using a "smart brute force algorithm"  (aka Min-Max search), the time complexity of the algorithm is O( B^n ). That is, you need around that B^n operations n-ply search.

An 8-ply search of a chess position would need to explore about 1.5 million possible paths! That is a LOT of work. Adding a ninth ply would make the tree balloon to about 50 million nodes, and a tenth, to an impossible 1.8 billion! A typical game has 30-40 moves, so you will need to search for 30^35 - 40^35 positions.

Assuming your CPU is running at 3GHz, and it takes only one clock cycle to analyze one position, it will take more than 1x10^42 years to complete the search.  So short answer is no.

However, endgames with small number of pieces have been thoroughly analyzed, and can be determined if mate is possible.  By August 2012, tablebases had solved chess for every position with up to seven pieces (According to wiki http://en.wikipedia.org/wiki/Endgame_tablebase)


One of the most common "unnatural" moves for a human is an under-developing move. Computers find them easily, as it's just another move to check but human's have invested time and energy developing a piece - why then move it back again?

Computers just crunch and then evaluate. Humans are much more emotive and have certain biases for development so it's very easy as a human to overlook a move that a computer would find in a heartbeat.

(one example might be re-routing a queen from one side of the board to the other, via the home-square - e.g. Qa5-d8-h4)

I realise this is a general answer but might help :)


Is using a 2D magnetic board in tournament play legal?

I'm pretty sure the rules of most serious tournaments prohibit the use of a second board for any reason, but I'm not sure if there are special provisions for people with disabilities and disadvantages.

As a player, I would be quite apprehensive towards playing someone who is using a second board, simply because it means I have to keep an eye out to ensure he is not cheating. I would certainly have a word with the arbiter if that situation were to occur.


How common/important is promotion to knight?

Well I definitely wouldn't put it as unacceptably incomplete, after all it is a very rare event that you're forced to underpromote into a knight, unless you're fooling around.

That said, there are cases in real games, where you actually have to promote knights (again very rarely, but still every now and then you see one of those), because e.g. you have to promote with a check (otherwise you may get checkmated), so if in such scenarios it's only with knight that you can check, then you really need the knight-promotion option. A random example:

[Title "1.e8=N+ Forced knight promotion"]
[StartFlipped "0"]
[fen "3K4/4P3/2qk4/8/8/8/8/8 w - - 0 1"]

1. e8=N+ (1.e8=Q Qc7#)

Here's another one: (match between Tomic vs. Winzbeck)

[Title "Forced N or B promotion else stalemate"]
[StartFlipped "0"]
[fen "3rb2k/2P4p/6pP/p2B1pP1/Pp2pP2/1P2K3/8/8 w - - 0 1"]

1. cxd8=N (1. cxd8=B) (1. cxd8=Q)

On the other hand, it may also happen that if you promote into anything else than knight, you stalemate the position, so again knight-promotion needed. You'll find tons of examples from this chess SE post and links therein.

Whereas if you take online blitz games as example, then most often (for time controls < 5 mins at least) players set their automatic promotion to queen so that in case they're in time trouble and have to promote, they can premove it.

All in all, I would say that you should try to implement it for completeness, and if it turns out difficult for you, then don't worry too much about it, no big deal.

I actually do recall a very fun game between Hikaru Nakamura and Boris Savchenko in the previous world blitz championship, where Nakamura had to underpromote into knight with check in order to avoid a mate in 1, here's the clip, it's only 2 minutes, watch it from the start, but if you just want to see the promotion moment, here it is.


List of openings for poor openings player

The openings I teach the kids at my club are typically the Kali and the London System, depending on what they answer when I ask whether they favor more the knight or the bishop, respectively. Both are structurally sound, from my experience, and typically do not require much book work.

If you're going for unsound openings that lead to tactical shots, hoping to get out of your opponent's opening knowledge, you might consider the Blackmar-Diemer Gambit (the opening I play most often - 1.d4 d5 2.e4?! dxe4 3.Nc3 Nf6 4.f3 often leads to a half-open f-file after O-O and a Ne5 post) or the Trompowsky Attack (the opening preferred by the leader of our chess club - 1.d4 Nf6 2.Bg5 and 3.Bxf6 with the idea being to double the f-pawns).

Take suggestions with a grain of salt. It's best to come to your own conclusions about which openings you prefer based on how comfortable you are in the middle-game of those openings. Take a look at each opening you find, try it out, and if it makes you smile unconsciously when you play it, you probably have the answer you're looking for.


I would recommend Silman's Complete Endgame Course which has a syllabus targeted by USCF rating as well as regular quizzes.


Theory: Things NOT to do in a concrete opening

This site has some material. Things like don't block your center pawns with your pieces, and don't play into fool's mates, etc.

Then there is a series of beginner-ish books from Pandolfini: Chess Openings: Traps And Zaps

also,
Win in the Opening: Opening Mistakes and How to Punish Them
by Yakov Neishtadt


What if threefold repetition occurs in WCC 2018?

Draw by mutual agreement is not allowed before move 30. But a draw by threefold repetition can be claimed at any point if it occurs.


You should always think how the last move played by your opponent has weakened his position.

In this game, f5 limits the mobility of the White king forcing it to stay confined in the g and h files.

That gives black a chance to checkmate using the rook and the queen. If the queen is moved the king can get to the f file and then it would be much more difficult to deliver checkmate. So you move the rook, and the solution is clearly the best choice because it forces white to exchange the queen to not get mated.


How do I make arrows and colored squares using Chesstempo's viewer?

I do not think that it is currently possible. Here is a list of features, and while a couple are close, that looks like a future enhancement. Here is a link to the original source.

Features in current version

Multiple games per PGN file
Multiple boards per page
PGN comments/annotations
Recursive Annotation Variations (i.e. alternative lines)
FEN tag supported for arbitrary starting positions
Support for subset of Numerical Annotation Glyphs (NAGs, e.g. ? !?)
Multiple board size and piece styles
Option for automatically playing through all game moves
Alternative move display formats
CSS controlled layout
Animated piece moves
Optional Row and column labels
Drag and drop piece moves (to make next move in game)
**Optional Highlighting of from/to squares
Optional Highlighting of valid squares when dragging pieces**
Display of taken pieces
Read moves from PGN file on server or embed PGN directly into webpage

Features to be added in future versions

Crosstable support
**Visual hints such as move direction arrows etc**
Record moves mode with PGN output
Allow embedded board snapshots in move display
Configurable Board flipping (current version auto-flips if first mover is black).


Can chess players agree to manipulate the results?

In a nutshell, current rules allow pretty much any sort of "spontaneous" agreement to a draw at the board, even if one side is staring at a forced mate in 6. If money changes hands or the results were agreed to before sitting down to play, it's a violation of the rules, but it's hard to enforce because folks who do that do it without witnesses to the act.

The "Sofia Rules" are an attempt to combat that, we'll see how long they last and whether they get applied to more than a few top tournaments.

If an official has evidence, he can declare a game forfeit, but that is subject to appeals where the evidence must be presented. If an official becomes known for doing it capriciously, no one comes to play; if a player gets the reputation for "selling points" he is often invited to play in tournaments where the goal is to get one or more players some title norms. So you can see the field is tilted in favor of the players. Not saying that's good or bad, just saying it is.


How many pawns make up for a missing queen in the endgame?

The simple and obvious answer is that it all depends on the position of black's pawns and king. In general the further up the board the pawns the better for black provided the king is in contact with the pawns, preferably in front of them.
Worth pointing out that the position you give is winning for white because the pawns aren't far enough forward. From what I said earlier it will be clear that white's first task is to separate black from the pawns, then win them.
This is how it is done.
[fen "8/8/8/6kp/p5p/8/K/6Q w - - 0 1"]

1. Qh2 {Cunningly not allowing the king to come forward} h4 2. Qe5+ Kg6 {Step 1 quickly accomplished. Black king separated from the pawns} 3. Qf4 Kh5 4. Qf5+ Kh6 5. Qxg4

and it is game over.
Move the kingside 2 rows forward, however, and best play is a draw, although white can give black opportunities to go wrong. At the same time white has to make sure black can't promote a pawn by checking, pinning or threatening mate.
[fen "8/8/8/8/p7/6kp/K5p/6Q w - - 0 1"]

1. Qe3+ Kh2 {only move} (1...Kh4?? 2. Qf2+ Kg4 3. Ka3  Kg5 4. Qg3+ Kf6 {anything else and Qxh3 will be check} 5. Kxa4 {and the king is going to come over and take the pawns}) 2. Qf4+ Kh1 {another only move} (2...Kg1?? 3. Qg3 Kf1 (3...h2 4. Qe1#) 4. Qxh3 Kf2 5. Qh4+ Kf1 6. Qf4+ Ke1 7. Qg3+ Kf1 8. Qf3+ Kg1 9. Ka3 Kh2 10. Qf4+ Kh1 11. Qh4+ Kg1 12. Kxa4 Kf1 13. Qf4+ {and repeating the process is going to bring the white king over to help and deliver mate}) 3. Qf3 Kh2 4. Qf4+

The two keys to playing these kinds of position are calculation and endgame knowledge. For instance in the second position it is key for black to stop white from winning the h pawn. That is because with just the g pawn black is lost. However replace the g pawn with either an h pawn or an f pawn and the position changes back into a draw.


Up to which rating is my strategy in the opening is applicable?

This is an opinion based question as there is no way to know.
For Bobby Fischer it might have been, but I met Bobby and know that he memorized all the openings.
Would it work for you?
My tournament experience says no.
These days there are too many people memorizing everything along with all the better training for tactics than when I learned.
Your more likely ceiling would be 1500, with possibly 1700 IF you were really good.
After that, positional play would start to be a factor and by 2000  most players would beat  you with traps, better/deeper tactics, or positional play.
And since they do know the openings they would come out of most of them with an edge in position as well as the initiative.  So just routine play would give them the edge to win if they were at 2000 already.  And if they do not beat you in the middle game with strategy then they will win in the endgame because they are far better than lower rated players at endgames.
If you want to make even uscf 2000 let alone ELO 2000 you will have to specialize in ONE opening for white and one for black and become so familiar with them that you do not need to memorize them as the moves will be obvious because you do understand them.  And you will have to be totally fluent with ALL tactical motifs and recognize them in different game settings.


After some searching, it seems that this composition is the current record holder. 218 moves; legal position with promotions:

R6R/3Q4/1Q4Q1/4Q3/2Q4Q/Q4Q2/pp1Q4/kBNN1KB1 w - - 0 1

Another version of the position (same number of moves):

3Q4/1Q4Q1/4Q3/2Q4R/Q4Q2/3Q4/1Q4Rp/1K1BBNNk w - - 0 1

Bonus:

79 moves (for black); from actual game between Davis and Panchanathan, source from Tim Krabbe's list of chess records:

4r1k1/p4pp1/2n2n1B/2b5/N6Q/P2q1N2/1r4PP/R4R1K w - - 0 1

99 moves (for white); all pieces on board:

q2Q3r/n6R/kpB1N1K1/p1p1Bppp/1PN3P1/1n1pp1b1/P1PPPP1P/r5Rb w - - 0 1

164 moves (both sides counted); all pieces on board:

R6R/pbpppK2/1B1QNNp1/1p3p1p/P1P3P1/1Pnnq1b1/2kPPPBP/r6r w - - 0 1

324 moves (both sides counted):

1QqQqQq1/r6Q/Q6q/q6Q/B2q4/q6Q/k6K/1qQ1QqRb w - - 0 1

412 moves (both sides counted); a curiosity, illegal position:

QQqQqQqq/q6Q/Q6q/q6Q/Q6q/q6Q/Q6q/QqQqQqQq w - - 0 1

Main source: Guide to Fairy Chess. The book is a bit old, so there might be new record holders, but if that's the case, I was unable to find them.


Can we say for sure that Black's king has not moved?

The conditions you gave are incomplete. The conditions include that black (to move) can castle; it's hidden in Smullyan's original problem text.

From the English book, last paragraph of the problem statement:

  Just then, however, news came that Black was about to castle. [...]

A clearer problem statement from the Retro Corner:

  Schwarz (am Zuge) darf noch rochieren. [...]

Black (to move) can still castle.


Where can I see the recorded chess matches?

This Week In Chess is probably the best place to go for those. New game files are posted weekly. Though in the case of Carlsen-Anand 2014, it's probably available from dozens of places, including the official website of the match itself: http://www.sochi2014.fide.com/results/


Is this queen endgame a win or a draw for White?

I analyzed your position with Stockfish 11 ("Stockfish_20011801_x64_modern" to be exact) to a depth of 78 and it returned the following line as the best continuation.
6k1/8/4qp1p/7P/6P1/5P2/6K1/Q7 w - - 0 1

1. Qa8+ Kf7 2. Qb7+ Kg8 3.Qb8+ Kf7 4. Qb1 Qe2+ 5. Kg3 Qe5+ 6. Kf2 Qh2+ 7. Ke3 Qe5+ 8. Qe4 Qc5+ 9. Ke2 Qb5+ 10. Kf2 Qb2+ 11. Kg3 Qa1 12. Qc4+ Ke7 13. Qc7+ Ke6 14. Kg2 Qb2+ 15.Kh3 Qf2 16. Qc4+ Kd6 17. Qe4 Qg1 18. Qb4+ Ke6 19. Qc4+ Ke7 20. Qd3 Qh1+ 21.Kg3 Qa1 22. Qe3+ Kd7 23. Qe4 Qa5 24. Qd3+ Ke6 25. Qe3+ Kd7 26.Kh3 Qb5 27.Qe4 Qf1+ 28. Kg3 Kd6 29. Kf4 Qb5 30. Qd4+ Ke7 31.Qe3+ Kf7 32.Kg3 Qb8+ 33.Qf4 Qb6 34. Qc4+ Kg7 35. Kf4 Qb8+ 36. Ke3 Qa7+ 37. Qd4 Qb7 38.Kf2 Qc7 39.Qb4 Qh2+ 40. Ke3 Qg1+ 41. Ke4 Qa7 42. Qd6 Qa4+ 43. Ke3 Qb3+ 44.Qd3 Qe6+ 45. Kd2 Qa2+ 46. Ke1 Qa1+ 47. Kf2 Qb2+ 48. Kg3 Qb8+ 49. Kg2 Kf7 *

As you can see by playing through the variation, no progress ends up being made and the game one way or another ends up drawn through the 50-move rule (I say one way or another because white theoretically could push say the f pawn at the end of the variation showed and restart the 50-move rule).


After 1...Bd5, Black can win at least a pawn. White cannot take on d5 because that's a clearly won king endgame for Black- Black threatens to go Kd4-Kd3-c2 and take the pawn on b2. If White tries to defend with Ke2, then Ke4 from Black wins the g-pawn and the game.


Avoid queen mating on g2 is easy:

f3, Qg3, Qh3+ are decent options
Re4, Kf1 also prevent immediate mate but are not good

Winning this position is objectively speaking impossible. Black is up a piece and white does not have sufficient compensation for it. Most players would resign if playing somebody of 1800 strength or even less.
If black is a beginner and/or short on time white could try to continue the game. The usual plan in lost positions with material down is to keep the position as complicated as possible and to avoid trades. You want to activate your pieces and start to attack something, specifically the enemy king.
In this regard one possible plan could be:

Qg3 (protects g2, attacks g7 and eyes c7), also makes space for the c pawn to move (clearance),
Bf4 develops the bishop a tempo by double-attacking c7. Also makes space for a rook to move to c1 (clearance)
Rac1 and 4. c4 or even immediately 3. c4 with the idea that after Qxc4 you play Rac1 and have a half-open file with attacking chances on the king

Once you get in c4 you can follow up with d5 which limits the range of the only active black minor piece.
Of course black also makes moves in-between and could spoil this plan.
The following example continuation is not best play, but about the best white could hope for for the next couple of moves:
[FEN "1nkr2nr/ppp3pp/2b2p2/3q4/3P4/1NQ5/P1P2PPP/R1B1R1K1 w - - 0 1"]

1. Qg3 g6 2. Bf4 Na6 3. Rac1 Kb8 4. c4 Qf7
5. d5 Ba4 6. Nd4

The final position is still lost for white, but at least white got the more active pieces and more space than black. There could be some attacking potential along the b file as well, now that the bishop left c6.


What's the verdict with Qa5 in the Accelerated Dragon?

In master level games (2400+ for both) 8. 0-0 is the only move.

White scores rather too well (34% wins) after 0-0, with black having 15% wins.

Including lower rated players white scores 38% wins vs 28% wins for black after 8.0-0. Thus this is very playable at lower levels.

Now about 8. ... Qb4 it appears dubious at higher levels but worth the shot in a regular game.

The sole high level game Solak (2566) vs. Djukic (2402) Serbian Ch 2007 proceeded as follows:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[White "Solak, Dragan"]
[Black "Djukic, Zeljko"]
[Date "2007.08.29"]
[WhiteElo "2566"]
[BlackElo "2402"]

1. e4 c5 2. Nc3 g6 3. Nf3 Bg7 4. d4 cxd4 5. Nxd4 Nc6 6. Be3 Nf6 7. Bc4 Qa5 8.  O-O Qb4 9. Qe2 Ng4 10. Nd5 Qd6 11. Qxg4 Bxd4 12. Bxd4 Nxd4 13. Rad1 Qc5 14. e5  Ne6 15. b4 Qc6 16. Bb3 h5 17. Qh4 g5 18. Qe4 a5 19. a3 axb4 20. axb4 b5? 21.  Nf6!+ exf6 22. Bd5  1-0

and white converted his exchange, overall very uncomfortable game for black even without blunder.

Also 9. Bb3 seems good for white too as 9. ... Nxe4 appears bad:

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[White "Hofmann, Brigitte"]
[Black "Kratochvilova, Magdalena"]
[Date "1973.06.??"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 Bg7 6. Be3 Nf6 7. Bc4 Qa5 8.  O-O Qb4 9. Bb3 Nxe4 10. Nxc6 dxc6 11. a3 Nxc3 12. Qf3! Ne2+ 13. Kh1! Qh4 14.  Qxf7+ Kd8 15. Qxg7 Bh3 16. Qxh8+ Kc7 17. Qe5+ 1-0

Similar play proceeds after 10. .... bxc6

So if 9. .... Nxe4 is not playable then 8. ... Qb4 is questionable


What is the right path to be followed on Chess.com for learning Chess?

Have a look at The path of learning chess and see how you can match this with what chess.com offers.

Starting with tactics, a couple of basic general chess principles and playing slower time controls is probably a good start. Avoid learning openings by heart. Watch videos aimed at beginners on youtube, chess24 or any other website (there are questions on SE about recommended websites as well).

IMO there is so much free material for beginners out there that I'd rather invest the money in a good book or for joining a chess club than paying for some website.

Once you are beyond the beginner stage you will want to figure out your main weaknesses and work more on those. Having a stronger player look over your game is very useful in this respect.


Is there a word to count one moving by one player?

There is indeed such a word for so called "half-moves." The terminology used is the word ply. To speak of multiple ply, plies is used. One would refer to the move "e4" as the first ply of the game.  An example demonstration of it can be seen at work in CSE's very own diagram viewer.
Sometimes, a user wants to add a game to their post, but wants the diagram to start with a specified board position. For example, this question would look like the below picture without the word "ply" to refer to the wanted position.

But with the code [startply "38"] having four spaces in front of it, the page, when loaded, shows the position after Black's 19th moves, i.e. the 38th ply, and before White's 20th move, the 39th ply.

White's ply count will always be odd while Black's will always be even. Do note that while "half-move" is a broadly used term as well, it is basically a laymen's term, and "ply" is the offical one.


When Black opens with Nf6 after e4 - Beginner question

1.e4 Nf6 is called Alekhine Defence.
It's an hypermodern opening as it doesn't directly fight for the center but more aim to provoke weakness in White camp and then counter-attack.

Also White has several option, first he can try not to push by playing :
2.Nc3
2.Bc4 as after 2...Nxe4 White get back the pawn with 3.Bxf7 Kxf7 4.Qh5+ g6 5.Qd5+

Still, it's better to take the center :
2.e5 Nd5 and now White has to decide whether or not he will push his pawns, so 3 systems are relevant :

the modern approach, White delays c4 : 3.d4 d6 4.Nf3 just finishing his development without giving weakness
3.d4 d6 4.c4 Nb6 5.exd6 and now Black has a choice between ...exd6 or ...cxd6 depends where he wants to put his bishop f8.
the most agressiv : 3.d4 d6 4.c4 Nb6 5.f4 just taking as much space as possible, I think this is the most critical continuation.


As a programmer, trying to write a chess engine by Javascript which runs on client's browser is very interesting. It has only 1018 bytes!

The engine doesn't obey the rules thoroughly (however we can ignore at this time). On the other hand it plays immediately and doesn't consume time to find better moves. It just trying to avoid obvious and basic blunders and probably it can find mating moves.

I suspect it uses any popular approach such as min-max search trees to evaluate moves. It's a very simple program and most of newbies can defeat it easily.

So, if you're not a programmer and following for a chess engine, don't count it as a real chess program.


Chessmaster is such a program. It is a bit outdated now, but still very usable for the majority of people. The skill cap for the game is well beyond what most club players will ever reach in their lifetime. Some examples of opponents you can play

Imaginary - You can play in a Human vs Orc arena, against a commander of the opposing army. There are limited difficulties in this level, so you may have problems playing against the harder opponents. It is also not explicit about which opponents are hard, and which ones are easy, so you will have to test this yourself.
Fictional - There are hundreds of fictional people to play against. Each of them have a biography (if you care to immerse yourself) and a picture of a person to help you believe you are playing against an actual person. There are a wide variety of playing styles to help simulate the different kinds of human players you might play against.
Historical - There are many famous players who have been simulated into the game, including various versions of Josh Waitzkin at the age of 6 and beyond. Most of the historical players however will be playing at the maximum skill level of the game, since it will be trying to simulate the strength of Grandmasters.

I'd recommend playing against the fictional players, as they are entirely beatable once you learn the rules. You will start out with a rating (around 800 if you are new) and your rating will adjust as you play a few games.

Don't be disheartened if you lose your first few games, this happens to everybody. If you are serious about improving, you will learn something from each loss and eventually your rating will improve, and you can play against stronger opponents.


What is the correct way to play this endgame?

In the starting position you give it is easy for white to create a passed pawn on the kingside and more difficult for black to do the same on the queenside. To guarantee that black cannot create a queenside passed pawn you need to aim for this position:
[fen "4k3/1pp2ppp/p1p5/8/P1P1P3/1P6/5PPP/4K3 w - - 0 1"]

From here the win is still not easy or guaranteed but black has no prospects whatsoever and just has to try and find a way to draw.
White can ignore all black queenside pawn moves apart from captures. If black captures on the queenside then white recaptures leaving, again, a structure which does not allow the extra pawn to generate a passer. Otherwise white doesn't touch the queenside pawns and can concentrate on creating a kingside passed pawn.
Once a passed pawn is created white tries to push it as far up the board as possible before abandoning it to capture the queenside pawns while black captures the passer. Black's job is to stop this plan.


What proofs for refuted gambits are there?

As long as chess can't be calculated from beginning to end, it is very hard to scientifically prove an opening to be refuted (aside from lines that leave you with such hopeless situations like a bare king against king and rook, of course).

If you are satisfied with a less scientific proof, I'd say gambits are even less so refuted. In my opinion, nearly all gambits are playable, as long as you won't play it against a superhuman database/program or a world champion. In a practical sense, probably no gambit worth of having a name is refuted in the sense of not being playable. Even if a gambit is widely considered unsound and often results in a worse position, it might contain enough steam to give your chess skill ample opportunities to overpower your opponent.I even remember a game where I suffered terrible against the BDG because I didn't find any refutation over the board. I only won because my opponent terribly misplayed the late midgame, but from the opening point of view he should have won the game.

So my answer is: No gambit I know of is refuted to the degree of being unplayable.


I actually like playing against opponents who attempt to play the same way that I play with their color.

The important part however is to not follow your favorite lines to the very end. As you said, there is a reason you consider them worthwhile. Instead, use your knowledge about which moves you consider unpleasant when playing that variation. Chances are that your opponent, who apparently likes the style of a line you like, will dislike this deviation as well and will be just as uncomfortable as you. Keep calm, and you might be the one with the psychological high ground.

Playing against your own weapons also is a good way of sharpening them. Best case, one of your chess buddies plays the same variation. Then both of you can play a lot of practice games against each other starting with this variation with alternating colors and test possible ways your opponent might attempt to counter your strategy. I think you learn more by literally putting yourself in the opponent's skin and really trying to find winning moves against your variation rather than by just assuming their moves while exclusively playing your own side in training, which might lead to some bias ("hopefully he'll continue with this move in this line..").


What exactly happened in the Open World Blitz Championship in game Carlsen-Alireza?

As you said, Alireza Firouzja lost on time while he was trying to restore a piece he dropped. He appealed, but the appeal was denied.

It was denied for several reasons.

First, he appealed about Magnus uttering one frustrating word earlier in the game. That was denied because had he wanted to appeal that, he had to do it right then and there, but he did not.

He questioned whether the clock was in proper operating order, but that was also denied.

He was declared lost because, no matter how unlikely, there was a position that Magnus could mate him in.

  Paragraph 6.9 of the FIDE Laws of Chess state:

  The game is drawn, if the position is such that the opponent cannot
  checkmate the player’s king by any possible series of legal moves.

It is my understanding that the formal appeal was on the Magnus' utterance as Alireza Firouzja had already been shown the rule in the rule book, so I do not believe that he formally appealed that part of the ruling.


The black king threatens to escape via e4, so

8/2Q5/8/3k2K1/8/8/4NP2/8 w - - 3 13

1. f3 Ke6 {(forced)}
2. Nf4#

(sidenote: I'm really divided into putting the solution in a 'spoiler' block with >! (as is customary on Puzzles.SE)

   like this

and the current way, with a diagram to allow playback. It would be very nice if we could put the diagram inside the spoiler.)


Playing against machines will definitely help you get better at playing against machines.  If that's the goal, go for it.

If you want to get better at Chess, you need to play several slow serious games against human opponents (both slightly above and below your skill level) on a regular basis.

The metaphor here is picking up a "learn some language in 6 months" interactive audio/software course that you do solo vs. being thrown into a village where that  is all that people speak and your ability to survive and grow  is acquired organically by making mistakes, getting critiqued with regular feedback loops as well as the social osmosis that is typical of increasing competency in any learning fraternity.

Even the mighty self-taught Fischer visited the clubs and competed against the world's finest to get from good to better.

There's also an aspect of gamesmanship, learning how to use the clock under pressure, deceptive stratagems and sub-optimum "play the man" ideas like gambits that you will NEVER pick up when practicing against a machine.  Gaining experience and intuition in a very short window of time is best achieved with a human feedback loop to help you constantly identify your weaknesses and recommend avenues of play (openings, endings, middlegame strategy) that you are clearly missing.

With that being said, seeking out human opponents at any time control is fairly easy these days via your laptop/tablet/mobile device. For instance sites like Chess.com,  Playchess and the ICC provide mobile-friendly apps that you can certainly use to get some chess in at all times of the day against human opposition.

For your kind of ambition though,  start hitting your local clubs and find (and in some cases, pay) a strong mentor to review each and every slow game you play as often as possible.