Yes. I remembered seeing a Reddit post on this, so I looked it up;
From /u/MortalSisyphus on Reddit:

At the end of the day engines win and lose games against each other. Which means their analysis is "flawed" in the sense they don't have an infinite horizon. It says 0.27, but if the move ends up with an eventual loss then the analysis of that move wasn't actually 0.27, it was -100.
Of course it is more complicated than that since each move contributes slightly, but the point is the same. The engine does blunder, just not in the way humans typically blunder. The blunders are basically impossible to see even for a 3000+ engine, but if the move(s) lead to a loss it is a blunder.
It is possible that a human seeing 3 roughly equally assessed lines could use intuition to pick the one least likely to be a long-term blunder, meaning a strategic mistake.
And of course humans have highly advanced opening theory, which is probably where most human advantage comes from if the engines in question don't have a very strong book.

If you want to see some human-machine chess, look up some modern ICCF games - ICCF correspondence games are played with engine assistance.


I think there are several ways you benefit from endgame study.

Your middlegame can benefit: For a beginner player it is often easier to process an emptier board with few pieces. The limited move options and plans then can help to focus on main concepts or ideas.

For instance if you learn to mate K+R vs K, you will learn how the pieces move, which squares are "attacked" (unavailable to the enemy king) and that in order to win you need to checkmate (take away all possible moves from the king and attack it). Also you will learn about zugzwang. All of this can be useful in the middlegame as well.

As another example you will learn that isolated and other weak pawn structures are things you don't want to have in an endgame, so you will want to avoid them in the middlegame (unless you get another advantage in exchange).

Also the importance of piece activity is usually pronounced in endgames which could make you pay more attention to it in the opening/middlegame.

It can make you win equal positions (or hold lost positions) ...if you are much better in endgames than your opponent.

It can help you decide whether and how to change from middle to endgame If you know that an endgame position is won/lost/draw, you might or might not want to go for a line in the middlegame that leads to that endgame.


Let me start from top to bottom:

  It is important to play e4 or d4 to 'control the center'. Myth or reality?

Myth.

  Well, there are two premises in the question itself: 1) That e4 or d4 'controls the center'.

When you play 1.e4/d4 you do not control the center, you physically occupy it.

To control the center, you will need more than a single pawn move-you need certain amount of developed pieces coordinated to control certain central squares.

1.e4/d4 simply fights for the center, you can not control it with just one pawn move-wish if it was that easy :)

Most importantly-you can not control anything unless your opponent allows you to-you can only fight for it.

  Well, there are two premises in the question itself: ... 2) That 'Controlling the center'is something important.

It is of utmost importance in the opening, as it allows you to completely control the game development. Controlling the center allows you to orient your actions towards the wings without worrying that your opponent can counter-strike in the center-thus usually refuting your plan or at least getting the equal play.

Also, you can open or close the game when you seem fit which usually can decide the game to your favor-not to mention the speed which your pieces get when centralized, since they can reach any part of the board in relatively equal amount of moves, contrary to the pieces posted at the wing.If we have a knight on d4, he can reach both wings at relatively equal amount of moves, but if it is posted on h3 then he needs a lot of moves to reach queen side which sometimes proves fatal.

Also, controlling the center hinders the activity and coordination of the opponents pieces-which enables you to start preparing for an attack or at least to create some serious weaknesses in their position.

In short-controlling the center is of paramount importance from the start to the end of the game-just remember that controlling is not the same as occupying the center.

To be honest, I haven't seen the opening that controls the center-all the modern openings either:

Fight for it.
Divide the control-E.G. White controls d5 and e4 and Black controls d4 and e5, usually by blocking the center, or by exchanging central pawns.
One side "surrenders the center" giving the opponent space advantage, but in return gets huge pressure against that center from the sides or from the distance ( usually light pieces perform the pressure ).

  It appears to me that 'controlling the center' is the least of the benefits of a move like e4 or d4. The fact is that it becomes mandatory to play e4 or d4 if you want to develop both bishops along their long diagonals(c1-h6 diagonal or a6-f1 diagonal). This seems to be the most important benefit of e4/d4 IMO and not 'controlling the center'.

You are almost there-the point of e4/d4 is to decide how will you fight for the center which will directly decide what type of pace will that fight take. Since e4 gives free development of the pieces-but e4 pawn has no initial support-the emphasis in this types of positions is on speed. You must develop your pieces and rely on them to fight for the center. This usually leads to the scenarios described above under 1 and 3, second option being only seen in some variations of French defense and Caro-Kann.

Since White has the advantage of the first move, he is naturally faster, so another benefit of the e4 is the ability for him to play gambits-hoping to be the first one to get the initiative in the center-which he can not achieve without controlling the center.Just the fact that some of the gambits in that link are viable, solid openings can show you just how much the importance of the center control is.

In short-e4 is played to give you fast development of your pieces-which is always used in fight for the center ( see Alekhine's defense, Ruy Lopez among many others ).

On the other hand, d4 is a bit clumsy move for developing pieces ( the queen does not have any good square to be developed ), but d4 pawn has support from the start.

This reduces Blacks options and immediate counter-attack is impossible. This gives White great solidity in the center but slows down his game. Again, the goal is the same-control the center but this time the strategy that implements this idea changes:

Instead of fighting the opponents pieces/pawns, that fight for the center, with your own, you will first occupy the center with pawns-so you can get space advantage.Once you do that you will have the time to finish development. Black, on the other hand, has a limited choice here. He can not counter attack at d4 at once ( 11. ... Nc6 is useless, opposing to 1. ...Nf6 in the Alekhine's defense ), so he usually opts for pressuring White center with his light pieces from distance, and then engineers a flank counter attack. The positions are usually closed, since White blocks center most of the time, but sometimes division of control occurs ( some variations of the Nimzo-Indian defense are a good example ) which results in semi-open games.

To summarize:

Both moves are played with one thing in mind-to fight for the center. The only difference is in the way they implement the fight-with e4 you get speedy development but unstable center which results in a "fast paced" games, yet with d4 you get stable center which slows down the game.

In both cases Black and White fight for the center and the winner of that fight controls the center-which results in immediate advantage for him.

Since chess is a balanced game, if both sides play properly then nobody wins the fight, only one of the 3 scenarios listed above can occur.

  So while it may turn out that 1) e4 and 1) d4 give rise to good games for white I feel it may be more due to the rapid development which these moves allow rather than because these pawns 'control the center'.

Indeed. Just a small adjustment of your observation-quoting you:

So while it may turn out that 1) e4 and 1) d4 give rise to good games for white I feel it may be more due to the ability to beneficially deploy pieces to fight for the control of the center which these moves allow rather than because these pawns 'control the center'.

  Indeed, sometimes, these pawns can be an obstacle for white's own pieces.(I am looking at things from white's perspective but the same argument can be similarly posed from the black player's perspective as well.).

Exactly. The whole point of those moves is to enable other pieces to fight for the center. Which move you choose from those 2 is a matter of preference.

One thing for the end:

You can also fight for the center with light pieces only, making pawn thrusts later-after the position gets clarified and one such example is the Reti opening ( look at Reti's games to see what I exactly mean ).

Check out this section on Wikipedia( Control of the center ) and I think that this article also sheds some valuable light.

If you have further questions leave a comment-I will gladly help.

  Do post your thoughts on this.

You really should avoid discussions-here we strive for a single answer.

Best regards.


Is there chess software that allows storage and replay of media annotations?

I haven't worked with it in a while, but I remember Fritz letting you do that.


What's the most efficient way to get from 2000 to 2300?

Once you've reached a skill level like that one you have, it really depends on what you current flaws are!

The first step should be a deep analysis of your games (I mean a real self-made analysis, not checking what Stockfish thinks of each position) Try to find the reasons why you lose the games you lose.

But, in general, for a 200+ rating point increase, you will have to work to some extent on all aspects of your game, with tactics and strategy (static and dynamic) being most important, but I'd also have a look at fundamental endgame theory as wel as build a solid opening repertoire.

Also, is it a possibility to hire a coach?

Good luck!


Adventures from the ODCL - How To Play The Endgame?

End games are my weakness and I ended up drawing this one. How should
  white go about things from the final position? What principles should
  I be applying?

The key features in the final position are:

1) You are a bishop for a pawn up

2) He has more weaknesses than you - 3 pawn islands to your 2

3) His king is much more active. It is ideally placed for action in the centre of the board while yours is stuck in the corner. This plus his passed e pawn are big pluses for him.

4) There aren't many pawns left. If they all come off it will be a draw.

Your aims should be, going from general to specific:

1) Play actively with your pieces to attack his pawns rather than passively defend if you can

2) Activate your king. His pawn on h4 is a big problem. If he can keep it and get his rook to the second rank then your king, your second most powerful piece, will be a spectator.

3) Avoid pawn exchanges.

4) Win the h4 pawn (I don't think he can stop you)

5) Blockade or win the e pawn

6) Queen either your g or h pawn

Without putting it through an engine I would suggest something like:

32 ... Rh6 - he isn't going to be able to save the h pawn

Rd8 (he wants to push his passed pawn) Rxh4
e5 Bd5 (blockading the e pawn and eyeing up the b pawn)
b6 (b5 would lose the a pawn after Rh6+) Rg4 (releasing the h pawn to run)

Push the h pawn, put your rook behind it on h4, move your king to where it is needed most. Not necessarily all in that order.


Is it OK to adjust your opponent's pieces, and what if he objects?

Is it OK per the rules to adjust your opponent's pieces?

YES

The rules are clear:

  4.2.1 Only the player having the move may adjust one or more pieces on their squares, provided that he first expresses his intention (for
  example by saying “j’adoube” or “I adjust”).

  4.2.2 Any other physical contact with a piece, except for clearly accidental contact, shall be considered to be intent.

When it is your turn, you may adjust the pieces. There is no distinction between your pieces and your opponent's pieces.

The next article makes it clear by implication that both your and your opponent's pieces are covered by this:

  4.3 Except as provided in Article 4.2, if the player having the move touches on the chessboard,with the intention of moving or capturing:

  4.3.1 one or more of his own pieces, he must move the first piece touched that can be moved

  4.3.2 one or more of his opponent’s pieces, he must capture the first piece touched that can be captured

  4.3.3 one or more pieces of each colour, he must capture the first touched opponent’s piece with his first touched piece or, if this is
  illegal, move or capture the first piece touched that can be moved or
  captured. If it is unclear whether the player’s own piece or his
  opponent’s was touched first, the player’s own piece shall be
  considered to have been touched before his opponent’s.

If you touch one of your opponent's pieces without saying "I adjust", or the equivalent in your language, then you must capture it. By implication, if you did say "I adjust" or "j'adoube", then you may adjust it.

  What if he objects?

Call the arbiter. Make sure you ask for extra time (2 minutes) for the disturbance your opponent caused you. A good arbiter should give you this automatically unless there were extenuating circumstances.

  When it is his move, he can readjust them to be off-center?

As long as he first says "I adjust" or "j'adoube".

Once, in a mischievous mood, when helping the arbiter set up the room before playing in a competition I deliberately positioned the knights, on all the boards I set up, either one facing forward and one backward or the left knight facing left and the right knight facing right (i.e. both knights facing away from the action). Most of the players, being at least mildly OCD, would have adjusted the pieces before the game, regardless, even if the pieces were perfectly placed :-).


For computer engines it is much harder to simulate a "human" style than just playing good. If you want to improve your play against humans, play against humans. Use the engines to analyze your games. As already commented, fast or blitz games (but please not faster that ~5 min, as the "quality" of the games decreases rapidly at this point) are a good way to learn to "see" quickly dangers and opportunities, and to have more tactics as usual on the board (as positional play becomes only important after you don't lose most games tactically).

I recommend lichess.org, which is free and offers (at least) three nice features: Computer assisted error checking after games, training positions from real games, and invitation by eMail


Do grandmasters ever disagree on what the main purpose of a move was?

The short answer is "Yes, they most certainly do". Not only that but they often disagree on whether the move is a good move or a bad move! This kind of thing comes from players and annotators having preconceived ideas about the players whose games they are annotating rather than because they are trying to deceive possible future opponents or keep important analysis secret. Players who still have such secrets to keep rarely if ever annotate games and if they do will be mostly bland and just follow the kind of analysis you would get from a computer.

Here is a concrete example of some very explicit disagreement from John Nunn's latest book "John Nunn's Chess Course". It's worth quickly saying that it's not really a chess course. Rather it is an excuse for John Nunn to publish very detailed analyses of some of Lasker's games disguised as a chess course ;-).

  The second example is from much later in Lasker's career ...

  It shows how once a narrative is accepted, the analysis is then
  shoehorned into being consistent with it and objectivity is thrown out
  of the window. The numerous spurious improvements for Black bear
  witness to the power of the consensus and only serve to obscure the
  real point that Lasker skillfully led the game into a deceptive
  position that appeared much better for Black but was not.

  This time the references are to Why Lasker Matters by Soltis
  (Batsford, 2005) and Emanuel Lasker Games 1904 - 1940 by Soloviov
  (Chess Stars, 1998). ... This is another game which has been
  considered little more than a swindle, and it's interesting to see how
  Soltis and Soloviov jump through all sorts of analytical hoops in
  order to keep the narrative intact.

There then follows a detailed analysis of the game interspersed with criticism for Soltis and Soloviov for just getting the analysis wrong. Nunn clearly has a very high opinion of the longest reigning world champion and believes that critics have often done Lasker an injustice which he puts right.

Note that the analysis that Nunn takes issue with is relatively modern. It is not that computers weren't available in 1998 and 2005 for Soloviov and Soltis to use to check their analyses rather that they neglected to use them because they had already made up their minds!


How can we convert PGN format to Resource Description Framework (RDF)?

I do maintain that converter at UPM.
You may also want to read the (highly technical) related papers:

An Ontology Design Pattern for Chess Games
Pattern-Based Linked Data Publication: The Linked Chess Dataset Case


Is there any website or software that are like "Guess the move" training program in chesstempo?

What about the iOS SmallChess app written by myself?

(source: smallchess.com)

(source: smallchess.com)

(source: smallchess.com)

(source: smallchess.com)


Should a player use the provided carbon copy sheet to record moves in a club/tournament?

According to the rules:

8.1.1 In the course of play each player is required to record his own moves and those of his opponent in the correct manner, move after move, as clearly and legibly as possible, in the algebraic notation (Appendix C), on the ‘scoresheet’ prescribed for the competition.

And also important:

8.3 The scoresheets are the property of the organiser of the competition.


Do most amateur players play aggressively?

That's a very broad and sweeping generalization because, for a start, the vast majority of chess players are amateurs. Very, very few are professionals. Very, very few can actually make a living from chess by playing, coaching or teaching. Not even all grandmasters can make a living from chess.
Then there is the biblical saying (from Ecclesiastes / Kohelet): "There is a time and place for everything under heaven." as immortalized by Mary Hopkins. On the chessboard too there is a time for aggression, a time for quiet development, a time for prophylaxis, etc., and a good player will be aggressive when the position calls for it.
So, I suspect the answer is "No", although it is probably true that most very weak players are over-aggressive. To understand why, it's worth looking at the major factors which separate very weak players from strong players:

Strong players understand one of the core principles of opening development: "First develop your pieces (trying not to move any piece twice until all the pieces have been developed) and only then think about attacking." (Nimzowitsch: "My System")
Probably the biggest difference between strong and weak players is not calculating ability but the ability to correctly evaluate a position. One of the saddest ways weaker players lose to stronger players is by doing some calculations and evaluating the resulting position as equal while the stronger players evaluate the position as materially equal but positionally crushing. That position is duly reached and the weaker player is crushed without ever knowing why (unless they ask the other player during the postmortem). Hint: when you lose to a stronger player in a serious game always ask for a postmortem if there is time.
Strong players play prophylactically (again Nimzowitsch: "My System"). Once past their opening knowledge they continually ask after every opposition move "Why was that move played? What are the plans? How can I stop them?". The weak player rarely does this unless the opponent makes a very obvious move threatening a capture or mate.


Why do masters open 1.d4 more often than 1.c4?

This has nothing to do with 1.d4 being an objectively better move than 1.c4. The moves are just about as good as one another, and sometimes even transpose as you've noted.

But 1.d4 was historically considered to be one of the two best opening moves (together with 1.e4) for a very long time, and it is more in line with the basic opening principles that beginners are typically taught.

So I'd reckon that it comes down to more players being introduced to 1.d4 early on in their chess career than 1.c4, coupled with the fact that old habits die hard (even for chessplayers).

However, one point that speaks in favour for 1.d4 over 1.c4 is that 1.d4 hinders black from playing 1...e5. You've noted that 1.c4, e5 is a reverse Sicilian, but I think that it is important to remember that the Sicilian is an opening that Black chooses to enter. In the opening Black is fighting for equality, and this is the case for the Sicilian as well, so saying that 1.c4, e5 is an improved version of it for White is basically just another way of saying that White is fighting for an advantage when playing it. But this is just what you'd expect from any good opening for White.

I'd go so far as to say that this way of arguing for a move is a fallacy in some sense, since it could be used to try and justify almost any first move for White as the best one (for instance, 1.Nf3 must be very strong since 1.Nf3, d5 is a reverse Nimzo/King's/Queen's/Bogo/whatever Indian defence and thus comes with an extra tempo as compared with the normal Indian defences, which are considered to be good for black). I'm almost tempted to name this way of  reasoning "The Reverse Sicilian Fallacy" for future use, since I've seen it more than once when commentators try to describe the virtues of 1.c4.


Is a "Strong King" handicap really as powerful as is claimed?

It depends on how we measure the effectiveness of a handicap. Here's what I mean by that:

If we are trying to increase the likelihood that the weaker player wins, queen-side odds are more effective than the strong king, because the weaker player has so much offensive potential in queen-side odds (and the stronger player doesn't have much defense).

If we are trying to decrease the likelihood that the weaker player loses, the strong king is more effective than queen-side odds, because the weaker player has so much more defensive potential in a strong king. Checkmating that king is one heck of a job.


How was the Candidate chosen for 1927, and why not sooner?

How was the candidate chosen?

Very simple. Money. The first to raise the $10,000 stake.

And when?

As soon as possible.

Was it some round robin format?

No. First to put $10,000 on the table gets to play the match.

Was there no Candidates Tourney at all back then?

Correct
This is explicitly stated in the Wikipedia article you reference:

From 1886 to 1946, the champion set the terms, requiring any challenger to raise a sizable stake and defeat the champion in a match in order to become the new world champion


Did Bobby Fischer actually write "Bobby Fischer Teaches Chess"?

Basically, no.

It was co-authored by Stuart Margulies and Don Mosenfelder, and while Fischer may have contributed a little, it is generally accepted that he just lent his name to the project.

Soltis, Andrew (2003). Bobby Fischer Rediscovered. B.T. Batsford Ltd. p. 10. ISBN 0-7134-8846-8.


What are good strategies or principles to prolonging the first stage of a game?

Is there a particular strategy or principle you can use to drag out
  the first stage of a game?

  One way I can imagine this being useful, if early on you exchange your
  bishop for an opponent's knight, having a crowded board would thus
  become in your best interest, as knights are generally more valuable
  on crowded boards. (Or so I am told)

This entire question is unclear, but I will give it a try to answer. Let us start one by one:

  Is there a particular strategy or principle you can use to drag out
  the first stage of a game?

Now why would you want to do that?

  One way I can imagine this being useful, if early on you exchange your
  bishop for an opponent's knight, having a crowded board would thus
  become in your best interest, as knights are generally more valuable
  on crowded boards. (Or so I am told)

Aha! So you wish to keep the board crowded in order to exploit the "advantage" knight has over a bishop!

Well, it is time to answer:

You can not keep the board crowded unless both you and your opponent "agree" to do so.

He can always try to exchange pieces and reduce the tension if he chooses, and the best thing you can do is to try and stop him by making the exchanges unfavorable for him.

Unfortunately, the opening theory has advanced a lot, and there are ways for both sides to obtain a good game, so the above plan will be very hard, if not impossible, to execute.

Another thing: simply exchanging the bishop for a knight, and trying to keep the pieces on board will not give you an advantage. It will all boil down to the placement of your pieces. By the way, exchanging the bishop for a knight early leaves your opponent with the bishop pair, which may give him the advantage.

I would strongly suggest you to find a resource ( book/online tutorial ) for playing the opening.

EDIT IN RESPONSE TO THE OP's EDIT:

  Why do you want to avoid exchanges?

  To see if it is possible to avoid exchanges without hurting your
  positioning, or by only hurting it in an insignificantly marginal
  manner.

This is not possible, I am afraid. You will have to exchange at some point and here is why:

When amateur wants to exchange pieces, he uses his own to "chase" the opposing one until the exchange has been made.

Master, on the other hand, puts the piece he wants to exchange on the strong squares, thus forcing the exchange. That way the piece becomes annoying and strong and opponent is forced to exchange it or else he will stand worse.

In a strong game, versus strong opponent you will not be able to dodge the exchange.

  What is your goal?

  To prolong the game. Perhaps if it were a game of speed-chess, and you
  wished to run down the clock to play for a draw; this could be a good
  strategy. Perhaps if you knew your opponent to be impatient, this
  could be effective against him.

This is very much possible, but you will need to play typical middlegame positions in order to achieve this. Furthermore, you will need to be the one who dictates the game. This is very important requirement.

You can play positions with an isolated pawn. My answer provides comprehensive coverage of the plans for both sides. Still, let me remind you-side with the isolated pawn exchanges pieces only when it can get a definite, visible-with-the-naked-eye benefit. As long as the board is packed with pieces the advantage is on its side. Side without isolated pawn strives to exchange minor pieces and enter endgame. Again, in the endgame you can prolong the game as much as you want as you will have the advantage. Usually you will be the only one who can play for a win and your opponent usually will have no counterplay but will be forced to passively defend.

Another typical position that has a lot of maneuvering and is slow is Carlsbad pawn structure and it arises from Queen's Gambit Declined after White exchanges on d5 with the move cxd5. White again has lots of plans here, but you would be interested in minority attack. Minority attack creates a weak pawn for Black on c6 and allows White to perform long maneuvers in order to take it ( just don't underestimate Black's mating attack on the kingside! ). This would be ideal choice for you.

You could try French defense with both colors. With White you can try Advance variation, and with Black Winaver sounds good. Again, both positions require long maneuvers.

END OF EDIT:

Best regards.


Does the Réti opening continuing to evolve?

I do not think that white has any advantage in the Reti, especially after 2...d4.

AlphaZero taught us that space is very important, probably even more important than we previously thought, and with 2...d4, black gains space. Stockfish 11 says that black has a -.38 advantage at a depth of 32, which needs to be taken with a grain of salt as it probably will dissipate as they get further into the opening, but it probably does indicate that black is absolutely equal.

In addition, in practical play, according to the Mega 2020 database, after 2...d4, white has a miserable winning percentage of only 46.9%.

That last statistic probably indicates that Horowitz was correct in that it is not the best opening (it is also not horrible), but you also need to keep in mind that unless you play very strong masters, you are probably fine to play it, although if you think you might get to that level in the future, then you also do not want to have to rework your openings totally when you get there.


No, they don't, because it wouldn't be fair. According to Wikipedia:

  A recent top chess engine, Rybka, has an estimated Elo rating of about 3200 (when running on an up-to-date PC, as computed by SSDF).

This is about 500-600 points higher than an average grandmaster (rating 2600-2700). This would be the same rating difference as between a grandmaster and a top club player (2000-2200) - it is a totally different playing category.

According to how the ELO rating is set up, the expected score of a 2600 grandmaster vs. a 3200 computer is 3% - i.e. when they play 100 games, the grandmaster is expected to draw only 6 games. This is way too low to be interesting.


How to get static evaluation from Stockfish in case that a king is in check?

If a king is in check, that's a major thing. There are likely to be few legal replies for the engine to consider. It's also unlikely (although possible) that there would be a large chain of checks from both sides. And it's very unlikely that you'd want to immediately prune the check; they're almost always worth at least considering.
When the engine is evaluating lots of positions, it therefore makes sense for it to not waste time evaluating the check position itself. Instead it's quicker to look ahead to how the check is resolved.


Database of analysed positions with corresponding scores

Here you can find a database with 50,000 games and engine scores after every move. That should translate to 80*50,000 = 4 million positions. Unfortunately the engine evaluations are by stockfish with only one second per position, which isn't very much.

You might also try to parse the Chessok Opening Tree, or to get the commercial version of it. Those evaluations are possibly better.


How to detect invalid pawn structures (not based on opponent material) for FEN valdation?

There is at least one case where your method will fail: pawns on f2, g3, h2 and  h3.

The structure is illegal, but drawing triangles from every pawn will not show this. To catch this, you'd have to draw the triangle from every square of the chessboard (h4 in this case demonstrates the illegality).

So as you said, draw triangles, but instead of starting from pawns, draw them from every square on the board. (For white, it actually suffices to try every square from the 3rd to the 8th rank.)


First you should make sure you master the fundamental concepts of opening play. Once you understand those concepts most openings can be universally understood just based on those concepts alone. It's unnecessary (and impractical) to try to classify every opening as having "x - y - z" specific ideas related to it, especially if you're a beginner.

But I believe it's a counterproductive approach to try to "learn openings". You're better off just learning Chess, and the openings will simply come naturally. Yes, there are repeating themes in certain openings, but if you want to truly master the openings those themes should always be readily explainable by general understanding.

Only then do you research the specific lines of an opening and commit them to memory. As for a roundup of all the available openings, you can always just look at Wikipedia. http://en.wikipedia.org/wiki/Chess_opening


What happened in this game between Hong Li and Sandor Farago in the FSIM November 2018?

Best guess: the mistake occured before, on move 15

Entry errors are frequent when games are entered into a software, especially if they are not entered by one of the players.

Here the operator must have made an error before move 19, reached an anomaly, and couldn't solve the mystery (or didn't have time to try, there are other games to be saved). In such occurence, entering a null move solves the issue, even if it makes some future users wonder what exactly happened during the game.

Only one of the players, or someone with access to the handwritten gamescore, could answer with 100% certainty, so I cannot be totally affirmative, but I am pretty sure the error occured on move 15. This must be how the game went:

[Event "FSIM November 2018"]
[Site "Budapest HUN"]
[Date "2018.11.06"]
[Round "4.4"]
[White "Farago, Sandor"]
[Black "Li, Hong"]
[Result "1-0"]
[WhiteElo "2216"]
[BlackElo "2337"]
[ECO "B80"]
[EventDate "2018.11.03"]
[FEN ""]

1.e4 c5 2.Nf3 d6 3.d4 Nf6 4.Nc3 cxd4 5.Nxd4 a6 6.f3 e6 7.Be3 b5 8.a3 Bb7
9.g4 h6 10.h4 Nc6 11.Nxc6 Bxc6 12.Rg1 Nd7 13.g5 hxg5 14.hxg5 Be7 15.Qd4
Rh7 16.O-O-O Nf8 17.f4 Qa5 18.f5 e5 19. Qd2 Nd7 20.Kb1 Rb8 21.Nd5 Qxd2 22.
Rxd2 Bxd5 23.Rxd5 Rh4 24.Bd3 Rh3 25.Ba7 Rb7 26.Bf2 Rh2 27.Be3 Rh3 28.Re1
Nb8 29.f6 gxf6 30.gxf6 Bxf6 31.Rxd6 Bg7 32.Rd5 Nc6 33.Bd2 f6 34.Rg1 1-0

15.Qd4, instead of 15.Qd2, is a very logical move, centralizing the queen and hitting the Pg7 left unprotected by Black's last move, 14...Bf8-e7. It is also a typical move when a Nd4-Nc6 exchange occurs in the Najdorf with the wQ still on d1.
It doesn't take a lot of stretch for an handwritten "Qd4" to be mistaken for "Qd2" (another plausible move) by the operator.
Then the operator won't meet any incoherence before move 19, when he finds 19.Qd2 written on the scoresheet but, puzzlingly, the queen already stands on d2. If the explanation doesn't jump to his eyes, using the null move feature of the software (most probably Chessbase) is the simplest way to deal with it. I have done that often myself when entering kids' games whose scoresheets I couldn't decipher.
By the way, 19.Qd2 is the obvious choice if the queen comes from d4, attacked by Black last move, 18...e6-e5. The whole game looks very coherent in this version (but that Black is positionnally outplayed pretty fast, with 22...Bxd5? a very suspect choice).
The most important argument in favor of 15.Qd4, in my opinion, is that it gives an explanation for the otherwise mysterious move 15...Rh7 played by Black: he simply protected his pawn. If 15.Qd2 had been played, 15...Rh7 would be a very, very weird decision (instead of any of the logical developing moves 15...Qc7, 15...Nf8, 15...Rc8, 15...Nb6, 15...g6 or 15....Qa5).


Validate Engine moves using Perft and divide

Q1

I wouldn't code up a new divide function because if you have a bug in your code, your new function will also be buggy.

Why don't you use Stockfish? Do you know you can run perft on Stockfish?

In Stockfish, run the following:

position fen r3k2r/1b4bq/8/8/8/8/7B/R3K2R w KQkq - 0 1
d
perft 3

You should get the following:

Position: 1/1
h2g1: 1160
h2g3: 1320
h2f4: 1444
....

===========================
Total time (ms) : 2
Nodes searched  : 27826
Nodes/second    : 13913000

Now you just need to add a std::cout to the perft function in search.cpp.

Find the function uint64_t Search::perft(Position& pos, Depth depth) { in search.cpp, then use it to print out all the positions in your perft search.

You can then compare your perft moves with Stockfish with the following Unix commands:

sort MyPerftMoves > MySortedPerftMoves
sort SFPerftMoves > SFSortedPerftMoves
diff MySortedPerftMoves SFSortedPerftMoves

Q2

You should use Zobrist hashing if you haven't. This is the standard technique for board representation in chess. In Stockfish, the code below does the trick for castling:

// Update castling rights if needed
if (st->castlingRights && (castlingRightsMask[from] | castlingRightsMask[to]))
{
    int cr = castlingRightsMask[from] | castlingRightsMask[to];
    k ^= Zobrist::castling[st->castlingRights & cr];
    st->castlingRights &= ~cr;
}

Your move representation should be able to tell you what castling move it is, and what castling rights (queen side? king side?) it has. This is implemented in Stockfish as castlingRightsMask[from] | castlingRightsMask[to]. Once you know your rights, you can just add it to your Zobrist key.


Several reasons I can see:

In closed positions like you have here, piece development is not as important as in open positions.
To me it seems that black played his King's Indian set up, more or less ignoring what white is playing, which generally is not a good idea.
Black should/could have attacked the center in the beginning more aggressively, thereby gaining space for his piece play. For instance 2. ... d5 would be natural (though likely he would have faced some version of the Blackmar-Diemer gambit). 5.... Nh5 would make any progress for white on the kingside very difficult.
Until around move 16 black played OK and should not be worse. White has gained lots of space, but, if black plays 16... axb5 he does not have any weaknesses, while white's pawns are soon getting weak (a5 and g5 are hanging, ...)
Around move 19, black has a clear advantage and should not have tried to hang on to the extra pawn but instead gone for active play, developing pieces, e.g. 19... Nf6 looks good.
Black might have missed the knight fork on e6 (i.e. might have missed that white is not forced to move the queen after 21...Nf6). Because of this, the whole plan with Bb7, Nf6 loses strength, because it just helps white to develop the knight to c3 (while the bishop on b7 is still not all that great).
28...Kd7 is the final blunder, though admittedly white's Nb5 is not that easy to see

So in summary I'd say: Black played too passively and missed some tactics.


Great Chess match resources (PGN) suggestions anyone?

The first site I'd recommend is Chessbase:

This site has a massive searchable database containing over 8 million games, including very recent matches, meaning at the time of this post 2016.  The interface is very well designed and feature rich (such as presenting per move statistics).  The site's authors do a reasonably good job of establishing comprehensive sets by pursing all extant copies of a particular player or tournament.

Although this database is essential, the site's features favour those who log in.  The basic account is free, and it's credentials are accepted at sister sites, however to getting PGN of particulars game you need a premium account.

  The second, more historical site to check out is ChessGames:

This site's vast database of historical chess games has over 812,000 games, all searchable via the sites Search feature.  Many of the not-so-recent historical games can be found in this gem-of-a-site.  That said, the games are accessible in PGN format one at a time.

  The third site to checkout, more specialized, is 365Chess:

Many players have seen as high-profile sponsors of top calibre competitions, or great match GM commentators. Accounts are free to create, and the site has other useful features such as the "Chess Opening Explorer" which allows you to create notes for particular openings (useful for study).

Also, the site presents a subset database of openings by players of 2400 ELO or more. The games included in the Masters Database are also part of the Big Database, but if you search or browse the database you'll obtain only games of the most talented masters.  This database is called "The Masters Database".

Another really nice feature is the ability to download all games by a particular player, but this feature requires a full membership, so not available to the free hobbyist.

  The fourth site to check out is PGN Mentor:

This site freely gives away complete sets of PGN games for specific players.  They download as .zip files.  Likewise, the site gives you the ability to download compilations of games categorized by opening. The sets you get aren't entirely current, and the sets not always complete (meaning important games for examples are left out), however they are free and generally pretty good.  That makes this site invaluable!

  Finally, check out Mark Weeks collection:

This is another recommended site with surprising curiosities such as Kasparov vs. IBM's Deep Blue and very early (historical) games.  The site is not fancy looking but nicely organized grouping by "Pre-FIDE" and "FIDE".  It claims to have millions of games, but honestly, I haven't yet given this site the attention it merits to get a sense of this.

  A recommendation that came from a read is This Week In Chess

This site keeps you up to date by delivering you Weekly updates, specifically, daily Chess news and games are in this weekly digest for download, by Mark Crowther. The site says "Every Monday The Week in Chess covers all the latest news and games from international chess. Download the zipped file of games in PGN or ChessBase (cbv is the modern format) format for reading off-line."

  If you have other recommendations and 'must have' sites that provide PGN resources, please


Which open source chess engine has the most positional understanding?

A really strong and great positional open source engine I have used is Rodent.  The last version was Rodent IV and is available at http://www.pkoziol.cal24.pl/rodent/rodent.htm
Of course Chess Programming wiki continues to be a good place to research and discover engines and the following link shows only open source engines.
https://www.chessprogramming.org/Category:Open_Source


Good books for- Grunfeild and Sicilian defence

There are many types of Sicilians so you should specify which one you intend to play,

But generally a good book is: Starting out: The Sicilian by John Emms

Although there are a whole multitude of excellent books written about specific Sicilians so if you could specify more than I could recommend some excellent books on those specific Sicilians.

For Grunfeld it's a little simpler, an excellent book is Understanding the Grunfeld by Jonathan Rowson, which is a very well regarded book.

There are many more excellent Grunfeld books but far too many to mention in this post.


How should I prevent the quality of my game from declining?

I have always found the fastest way to get rid of some rust to be tactics training.

I would recommend two steps:

First you do a lot of relatively simple exercises, like game typical 'mate in two' (not chess problems, those can be quite difficult). This will remind your brain to automatically spot the easy stuff and reduce the probability of really bad blunders. You can go through the same positions several times.

Then you do some hard problems with something like 15 minutes per problem, here every problem should be new to you, you should sit down with a clock and write down your solution. This should get you back into tournament shape.

In my experience this works a lot better than playing blitz online. Playing long games seriously should have a similar effect, but I usually want to get back into shape before I play a really serious game.


Najdorf poisoned pawn with or without 7..h6 8 Bh4

One reason is that it avoids a certain line that you would get after playing 7...Qb6, which is 8.Nb3

If Black plays 7...h6 first, 8.Bh4 Qb6 9.Nb3 is no longer possible because Black can play 9...Qe3+ winning the f4-pawn. This would not have been the case in the  7...Qb6 line since the bishop would have still been on g5, protecting the pawn.

Another reason is that sometimes Black would like to play ...g5.

[FEN ""]
1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6. Bg5 e6 7. f4 Qb6 (7...h6 8. Bh4 Qb6 9. Nb3 Qe3+ 10.Qe2 (10.Be2 Nxe4) 10...Qxf4) 8. Nb3 Be7 (8...Qe3+ 9.Qe2)


Looking for a PDF of the British Chess Magazine, Sep. 1907

First place to go is the Chess Archaeology web site, in particular the subsection
"Library" (URL: http://www.chessarch.com/library/library.shtml)
(You'll find two scans: one from Princeton, another from Stanford.)
Another useful source is the WorldCat library (URL: https://www.worldcat.org/). While it does list printed copies as well as copies on microform or in digital form, you can easily search only for digital copies (usually listed as eBooks, eMagazines or eJournals)
In this particular case, however, there seems to be no e-copies listed.


You can only make an illegal move by making a move. Pressing the clock without moving is not making a move. So the arbiter can't use that rule to make a decision.

There is FIDE rule 6.13 (chapter 6 is about the clock): "If an irregularity occurs and/or the pieces have to be restored to a previous position, the arbiter shall use his best judgement to determine the times to be shown on the clocks. He shall also, if necessary, adjust the clock’s move counter."

So the arbiter can use his best judgement to reinstate the correct clock times. This is of course unfortunate (it's hard to stay concentrated for the players, especially the innocent player), but the arbiter can't just invent rules.

If this happens regularly (the player is doing this on purpose), there is always article 12.8: "Persistent refusal by a player to comply with the Laws of Chess shall be penalised by loss of the game. The arbiter shall decide the score of the opponent."


What are the chess time limits used by FIDE?

Interestingly there are two FIDE documents specifying these. Fortunately they don't contradict each other.
First, FIDE Handbook - General Rules and Technical Recommendations for Tournaments / 07. Time Control / says:

There is a single time control for all major FIDE events: 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 starting from move one.

The list of FIDE events where this single time control will be used:
Chess Olympiads
World Team Championships
Continental Team Championships
World Cup
Continental Championships
Zonal Tournaments
World Youth & Junior Championships
Continental Youth & Junior Championships
World School Championships
Continental Club Championships

There are some obvious omissions here. What about the World Championships? The Women's World Championships? The Candidates? What about rapid and blitz championships?
Well, section 12 of FIDE Handbook C. General Rules and Technical Recommendations for Tournaments
02. Standards of Chess Equipment, venue for FIDE Tournaments, rate of play and tie-break regulations Approved by the 2018 FIDE General Assembly
taking effect from 1 July 2019 has a full list.

The following time controls are approved for FIDE World Events:
No EVENT TIME CONTROL
1 World Championship Match 100’/40+50’/20+15’/end with incr. 30”/move, starting from move 1
2 Candidates Tournament 100’/40+50’/20+15’/end with incr. 30”/move, starting from move 1
3 World Cup 90’/40+30’/end with incr. 30”/move, starting from move 1
4 Grand Prix 100’/40+50’/20+15’/end with incr. 30”/move, starting from move 1
5 Women’s World Championship Match 90’/40+30’/end with incr. 30”/move, starting from move 1
6 Chess Olympiad 90’/40+30’/end with incr. 30”/move, starting from move 1
7 World Team Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
8 Women’s World Team Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
9 Women’s Grand Prix 90’/40+30’/end with incr. 30”/move, starting from move 1
10 World Senior Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
11 World Senior Team Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
12 World Juniors and Girls U-20 Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
13 Continental Individual Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
14 Continental Team Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
15 World Youth 14-16-18 Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
16 World Cadets 08-10-12 Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
17 World Schools Individual Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
18 World Schools Team Championships 90’/40+30’/end with incr. 30”/move, starting from move 1
19 World Amateur Championship 90’/40+30’/end with incr. 30”/move, starting from move 1
20 World Olympiad U-16 90’/40+30’/end with incr. 30”/move, starting from move 1
21 World Rapid Championships 15’ with incr. 10” per move, starting from move 1
22 World Blitz Championships 3’ with incr. 2” per move, starting from move 1

Just to decipher what that means. Take -

1 World Championship Match 100’/40+50’/20+15’/end with incr. 30”/move, starting from move 1

This means that
There is a 30 second increment starting from move 1
The first 40 moves have to be played in 100 minutes
The next 20 moves have to be played in an additional 50 minutes
After this (so 60 moves already played) the players get an additional 15 minutes to complete the game


I checked with Stockfish and indeed there is no normal mate in one for White, and there isn't a mate in one for Black either. So this obviously a trick/joke problem.

The trick is this: What last move of Black would allow a mate in one?

Solution:

   The mate in one is “1. dxe6#” en passant! This move takes away the Black king's only flight square on h8, which is what stops any other attempts by White.

Explanation:

   The joke is that it can't be proved that Black's last move was “0... e5”. The accepted convention in chess problems is that an en passant capture is only allowed on the first move of the solution if it can be proved that the captured Black pawn made the double-step as Black's last move. It is obvious that Black has plenty of possible last moves other then e5, hence why this a trick problem.


Is 1.e4 the best first move for White from a theoretical point of view?

According to some GMs, d4 is the best first move.
Alekhine, commenting on a Slav in his greatest games book, claims it gives White more chances of gaining an advantage.  After taking the c pawn, Alekhine further comments that White now obtains an appreciable advantage. (Quoted by Hans Berliner.)
Hans Berliner, in his book The System--A World Champion's Approach to Chess, claims, and Fischer agrees, that the advantage of the first move is the ability to attack the opponent's pawn center first.  Since both agree that the King's Gambit is dubious, that leaves the Queen's Gambit as the only sound opening.

Many GMs have said d4 is better:  although they claim it is due to needing a deeper understanding of chess.  Anna Zatonskih states it better that you can make some minor inaccuracies and still have a good game.  In e4 games, one mistake could cost you the game.


How can a human figure out best move in this position?

Maybe before justifying the pawn sacs one should answer more convincingly why taking on c3 would not have pleased White. The answer is the backward pawn on c-file and future pressure against it by rooks from c-file. Black cannot be happier if the Queens get exchanged on c3 as well. So, taking the bishop back on c3 would have yielded nothing for White. b4 is half out of desperation as it is of creativity!

Augment to this the forcing sequence delineated by the other answers here, and you see that b4 is not as much of an abnormal move as it may look initially.


It's a very interesting position. From your description I see that you are on the right path of planning. Let's see:

Clearly your queen-side is safe enough (unless you lose a couple of tempos), and although your bishop is in a completely defensive position on the 8th rank, it has still kept its prospect for a possible attack on white's king-side. Furthermore your rooks are in the best positions, each fulfilling a role(not wasted necessarily) and safe from any harassment (Ne5 e.g. has no immediate threat for you). Finally your queen is active enough on e7.

Now that we have summarized in a rather crude manner our position, let's see how's white doing:

No real weakness in his position, his rooks seem to be looking at a wall as b7 is perfectly safe for now, his knight is in a dynamic enough position on f3 (many maneuvers possible) and he has a slight control on h7 but it doesn't really matter since his queen+bishop are being refuted by single knight on f8.

Now that we have a clear picture of what the situation on both sides is, let's see what we can use as leverage:

Your idea with g6 preparing Ne6 to Ng5 was not a bad plan at all, possibly even forced if you ask an engine, but I don't really like it: simple fact that if we're saying that white's heavy pieces are far from any defense and very inactive (queen on c2 not doing much as long as e.g. you keep control on e4 and h7 with your knight), so if we (as black) have any chance of playing actively, it has to have a really quick tempo or else white builds up an opening on e-file with Re1, Nd2 and e4 happens (he will even have rook on the 3rd rank which can be brought into a king-side attack if e4 happens). As your game shows, your idea was good, but white has enough time for a defensive build up.

My suggestion: start off immediately with g5, with the plan to follow up with h5, very crudely, gaining possible tempo on knight harassment on f3 and forcing an exchange on g4 to open up the h-file, again if in any scenario white's knight is either retreated or exchanged, it's good for us as white's pieces are too far off and we're ok with a king-side pawn expansion (whole idea: gain space on his weak side, force line opening), further ideas to notice:

Our bishop is always ready to contribute to the attack whenever needed.
once h5 is played the knight on f8 is freed up as well
kg7 is a likely move for us as white has no dark square control, so rook can swing eventually to h8
we have enough control on e-file, so white cannot really hope for a counter-attack
with g4 played so early, any Ne5 followed by f4 maneuver is avoided
Finally before getting into possible lines, note that our only idea is to take the initiative with any tempo we can find and hope that white under pressure will fall, I say "hope" because if you feed this position to an engine it's possible that it will see boring draws all around or even like white's position better, so since we're not playing against an engine, such approach does work very well. Lets analyse a couple of possible follow-ups:

First line:

[Title "1st variation after g5"]
[StartFlipped "0"]
[fen "2b1rnk1/1pr1qppp/p1p5/2Pp4/P2P4/1R1BPN1P/2Q2PP1/1R4K1 b - - 0 1"]

1... g5 2.a5 h5 3.Ne5 Nd7 4.Nxd7 Qxd7 5.Qe2 g4 6.h4 f5 7.g3 f4 8.gxf4 Qd8

With a very nice continuation for black, of course it's no checkmate anytime soon nor an easy win, but it's a position with solid attacking hopes for black.

[Title "2nd variation after g5"]
[StartFlipped "0"]
[fen "2b1rnk1/1pr1qppp/p1p5/2Pp4/P2P4/1R1BPN1P/2Q2PP1/1R4K1 b - - 0 1"]

1... g5 2.a5 h5 3.Qe2 g4 4.Ne5 Qg5 5.f4 Qe7 6.Bc2 f6 7.Ng6 Qg7

Again a position with a number of weaknesses in white's position and initiative in black's hands.

[Title "3rd variation after g5"]
[StartFlipped "0"]
[fen "2b1rnk1/1pr1qppp/p1p5/2Pp4/P2P4/1R1BPN1P/2Q2PP1/1R4K1 b - - 0 1"]

1... g5 2.Nh2 h5 3.Qe2 g4 4.hxg4 hxg4 5.Nxg4 Qh4 6.Ne5 f6 7.Ng6 Nxg6 8.Bxg6 Rg7 9.Bxe8 Rxg2+ 10.Kxg2 Bh3+ 11.Kh1 Bf1+ 12.Kg1 Bxe2

Again shows you how easy it is for white to go completely wrong in his defense. I think these 3 positions make it clear enough for your to see my idea basically, from this point it's more fruitful if we just keep discussing possible variations of any line you want, and don't hesitate asking any question regarding the positions or ideas discussed so far.


Is there any android app or software that allow me to create my own chess puzzle so I can solve or study it later on?

LiChess or Chess.com have apps accessible to Android, in which you can find an analysis board and study from there. You can save the boards as well until further use.
Plus, there are a lot of features, such as finishing game with computer, analysis from engine etc.


I got in touch with Bill Forster, the developer who created the software, and this is what he replied. It worked for me so I hope it will be useful for somebody else:

  I did some experiments with your use case and I admit it is hardly
  obvious how Tarrasch is handling your quite reasonable attempts - in
  fact what you are doing should really work, so sadly I must admit a
  bug.

  However there is a workaround - Start with the second variation first.
  Position the cursor just before the open parenthesis that introduces
  the second variation [so before "( 12...Ng4 etc"]. Then promote that
  with "Promote rest of comment to moves". Hopefully that will work.
  Then promote the 12...Qe7 variation. I think this method can be
  extended to any number of these kind of "peer" variations (by this I
  mean variations that are not subvariations). Promote the last one
  first and work backwards.

I tried this with more than two variations and going from the last to the first now as I go through the moves in all the variations the board gets updated accordingly.


How high is the level of professional blitz tournaments?

There is insufficient data to answer objectively. However, there are a few things that can be said with confidence:

a player's bullet rating should always be less than or equal to his standard rating, because more time allows for deeper middlegame calculations
you can't accurately predict a player's bullet rating by his standard rating and vice-versa
some chess clubs have formulas for matches with time handicap where the stronger player gets less time depending on the rating difference between his and the weaker player, but in most cases the stronger player is a strong bullet player too and wins anyway
grandmasters keep their knowledge of openings and endgames in bullet time controls
certain flawed strategies work better in bullet chess
there are many grandmasters out there who are critics of fast chess
there are many grandmasters out there who have a style incompatible with short time controls

To get the data to answer your question, you would probably need to examine a lot of games between players of similar strength where one plays standard and the other one plays bullet and see from the results if you can consistently find the rating gap, and there aren't many volunteers for that.


1 - Centralize and coordinate your pieces. This is when tactical opportunities will begin to materialize.

2 - When your position is cramped, exchange pieces.

3 - When ahead in material, exchange pieces, not pawns.

4 - When you have a bad or inactive piece, exchange it.

5 - Don't launch an attack on the flank until the centre is secure.

6 - When the opponent's king is exposed, look for tactics and combinations.

7 - When the opponent's development is poor, look for tactics and combinations.

8 - Attack your opponent's weak and backwards pawns.

9 - Occupy your opponent's weak squares. Knights are particularly good at establishing outposts.

10 - Don't make unnecessary pawn moves in front of your king. This weakens your position.


What are quick and easy ways to learn, and what should i focus on

A beginner should focus on playing games, solving tactic puzzles and playing through annotated master games.

If you play through master games with a real board instead of at the computer, you will quickly learn the notation as well.


how to evaluate the position inside the search function

where should I place checking for chaeck/stale mate

Right before make first move: there is no first move!


There are quite a few things to do to improve your results as well as enjoy the tournament.

On the physical side stay well rested and well hydrated during your game. Eat plenty but keep it healthy. When it's not your move walk around and look at other boards, resting your tired eyes and getting the blood circulating. Do a light exercise in the morning before your games even start. Lastly if you didn't sleep well maybe have some caffeine ready to go.

As for mentality, don't worry about anything except having interesting, exciting games you can show your chess friends when you get back from the tournament. Win or loss, make sure you play what you think are the best moves, even if they get very complex. Don't look at your opponents rating just briefly glance enough to see your board color and the table you're playing at. Knowing their rating and letting it distract you won't let you make better chess moves over the board. Keep your entire focus on the game you are playing. Once you finish a game, win or loss, don't think about it too much and relax. You just played a physically exhausting game, recupe the best you can and focus on getting your energy back. As long as you tried your best that's all that matters. Results are just check marks for one side or another, what really matters is being brave and showing determination to play the best move you can see, and improving your understanding using those games once the tournament ends.

At least I try to do all these things when I play tournament chess, I've even come first in my section a number of times.


The best thing to do is play some games with that specific time control so you can get used to the pace.

Whether to play positional or tactical is a decision around your skills and what you know about your opponents play.  Though it is considered more difficult to defend than attack and that can lead your opponent to use more time.  It is also true that finding a plan is time consuming; so I would just play toward your skills.   Certainly you should study a lot of tactics so you can calculate quickly.

In general, you don't want to fall behind on the clock.  But you shouldn't panic if you do.  And don't play on your opponents time pressure.   5 second increment is a lot.  You should get comfortable defending "drawn" endgames where you can make a move within 5 seconds.

Semi-dubious openings like the Smith-Morra Gambit are common in quick tournaments.  Prepare your openings so your opponents don't get to have any such fun!


No, it's not necessary. If the opponent doesn't notice it, it's their fault. Reasoning behind this is (probably) what happens if your opponent is not at the board when you make the move? You don't have to sit and wait for them (and stay away from the toilet...) just in order to inform them that you have just checked the king - which is something that any player should notice themselves anyway.

If the opponent doesn't notice and makes a move that doesn't prevent the check, there are procedures to correct this (and you should generally involve the arbiter in these).


One amazing game I know that ends in a pawn mate in one called The Polish Immortal in which Black sacrifices all four minor pieces to win the game! The pawn does a double-step to give the mate.
[Title "Glucksberg-Miguel Najdorf, Warsaw Poland, 1929, The Polish Immortal"]
[FEN ""]

1.d4 f5 2.c4 Nf6 3.Nc3 e6 4.Nf3 d5 5.e3 c6 6.Bd3 Bd6 7.O-O O-O 8.Ne2 Nbd7 9.Ng5 Bxh2+ 10.Kh1 Ng4 11.f4 Qe8 12.g3 Qh5 13.Kg2 Bg1 14.Nxg1 Qh2+ 15.Kf3 e5 16.dxe5 Ndxe5+ 17.fxe5 Nxe5+ 18.Kf4 Ng6+ 19.Kf3 f4 20.exf4 Bg4+ 21.Kxg4 Ne5+ 22.fxe5 h5#

Although it was a blitz game, this game ends in a nice discovered checkmate by a pawn.
[Title "Ely Sollano-Fedrick Rhine, Chicago USA, 1977"]
 [FEN ""]

1. d4 Nf6 2. Nc3 d5 3. Bg5 c5 4. Bxf6 exf6 5. dxc5 d4 6. Ne4 Bf5 7. Ng3 Bxc5 8. Nxf5 Qa5+ 9. c3 dxc3 10. b4 Bxb4 11. Qc2 Qxf5 12. Qxf5 c2#

Another pawn move that results in checkmate is promotion. While there are many such games that end with it, this game has a unique perk in that the mating move was done by the pawn that made the first move.
[Title "Bojan Kurajica-Michael Franklin, Hastings England, 1972"]
[FEN ""]

1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 e6 5.Nc3 Qc7 6.g3 a6 7.Bg2 Nf6 8.O-O Nxd4 9.Qxd4 Bc5 10.Bf4 d6 11.Qd2 h6 12.Rad1 e5 13.Be3 Bg4 14.Bxc5 dxc5 15.f3 Be6 16.f4 Rd8 17.Nd5 Bxd5 18.exd5 e4 19.c4 O-O 20.Rfe1 Rfe8 21.Qc2 Re7 22.Bxe4 Ne8 23.Bd3 Nd6 24.Re5 Rde8 25.Rde1 f6 26.R5e2 Kf8 27.Re6 Rxe6 28.dxe6 Ke7 29.Bf1 Kd8 30.Bg2 Qa5 31.Qf2 Ke7 32.b3 Nf5 33.Bxb7 Nd4 34.Bd5 Rd8 35.Rd1 Qb6 36.Qe3 a5 37.Qe4 a4 38.Qg6 axb3 39.Qf7+ Kd6 40.e7 Rd7 41.e8=N#

Another mating move that has actually happened is checkmate by en passant! Here is that earliest known and most beautiful known example of it.
[Title "Gunner Gundersen-A. H. Faul, Pietzcker Christmas Tournament, Melbourne Australia, 1928"]
[FEN ""]

1. e4 e6 2. d4 d5 3. e5 c5 4. c3 cxd4 5. cxd4 Bb4+ 6. Nc3 Nc6 7. Nf3 Nge7 8. Bd3 O-O 9. Bxh7+ Kxh7 10. Ng5+ Kg6 11. h4 Nxd4 12. Qg4 f5 13. h5+ Kh6 14. Nxe6+ g5 15. hxg6#

Lastly, although it is not from a game, here is a very pretty chess problem in which White sacrifices all eight pieces and and two pawns to give mate with a pawn!
[Title "Julio César Infantozzi, Mate In 16 Moves"]
[FEN "R1n2N2/4pk1B/2Q1r2B/2K2b2/Rr1n2P1/1q1P1PP1/4N2b/8 w - - 0 1"]

1. Qe8+ Kxe8 2. Rxc8+ Kf7 3. Bg8+ Kxg8 4. Ng6+ Kh7 5. Rh8+ Kxg6 6. Nf4+ Kf6 7. Rf8+ Ke5 8. Bg7+ Rf6 9. Bxf6+ exf6 10. Re8+ Ne6+ 11. Rxe6+ Qxe6 12. Ng6+ Bxg6  13. f4+ Rxf4 14. gxf4+ Bxf4 15. Re4+ Bxe4 16. d4


How to determine the value of a chess set?

The value of a set can be pretty arbitrary. Things that affect the cost of a set include:

the materials from which it's made
the amount of skilled hand-work
the quality of the components
its rarity
size
accessories

The travel set you posted is unremarkable with respect to the attributes above:
 - it's plastic
 - none
 - historically low
 - not at all
 - small
 - magnetic board and carrying case.

Now, the same set coming from, say Germany, would get similar remarks except for the "quality" rating. I'd expect that a set from Germany would be made of better components; thicker plastic, better glue, and more careful assembly.

Now, value is a tricky beast.  The hypothetical German set I mentioned might cost $30. The Chinese set could have the same or better value.  You won't know until it is in your hand. For $17, you'll probably have a set you can use for a year or two.  Who knows, though, it could be amazing and last forever. Or it could arrive broken. Who knows.

I don't know much about travel sets.  A webs search should tell you what's out there. Then you can compare features.

I think the most luxurious sets are coming out of the House of Staunton.  You'll see some amazing sets there. Be prepared for sticker shock.  My personal insane favorite would be the set made from mammoth ivory.

Bigger is not always better, rarer materials are not always more practical, fancy is not always better than simple. HoS has more affordable sets, though many would not consider them so. The Reykjavik set has always been a favorite of mine. Boxwood and ebony are to me the perfect woods and a 3.75" King is the perfect size. The design is clean. It's $350.

What makes these sets a good value is that the wood used is rare, suited for the task, and of high quality.  The workmanship is where it needs to be. Skilled people are carving the knights (in some cases), the size is correct, the weights are correct, the styles are correct (don't take your Star Trek themed set to a tournament...), and they simply feel good to touch.


A position in which there is no possible checkmate

I think that is limited to just a few positions.

A lone king vs. king.
king and bishop vs. king.
A king and bishop vs. king and same colored bishop as the other side.
A king and multiple bishops of the same color vs. king.
A king and knight vs. king.
Any barrier position, where neither side can cross over to the other side.

Even king and knight vs. king and knight you can get a mating position.

Here is a wonderful position that I "stole" from chess.com that illustrates why that FIDE rule exists. Yes, it was probably not fair for Carlsen to get the full point, but imagine having this position, and not getting the full point.

 [FEN "6rk/4NP2/7K/8/8/8/b7/8 w - - 0 1"]

  1. fxg8=Q+ Bxg8 {By USCF, and chess.com rules, this is a draw here.} 2. Ng6#

 [FEN "6nk/5N2/6K1/8/8/8/8/8 b - - 0 1"]


Huge difference between elometer.net approximation and other rating

I recently took the test and the result was reasonable (around 2100), so it is not complete bogus.

However I am rather skeptical about such tests, since I believe that playing strength/Elo rating depends on more factors than finding the best move in a certain position; such as the following which are not really tested at elometer as far as I can see:

Can you concentrate for 4-6 hours that a game can last?
Do you blunder often?
Can you come up with good long time plans in the middlegame?
How good is your opening knowledge?
Can you spot the point in a game where you need to find a good/special move, i.e. the point where you have to invest some time thinking vs following a certain plan more or less automatically?

Regarding your comparison of online rating (1400), expected Elo of 1400-1500 and the elometer estimate of 1950, a few thoughts:

Any rating system is only relative to the pool of people playing. You cannot compare online ratings from one website with online ratings from another website or with the FIDE Elo.
You say your online rating is from 3 days/move game, which is a big difference to the Elo which is from normal games with hour long time scale.
In my experience players of your strength, particularly if they are beginning with chess, are not very stable in their playing strength. One game they might play like a grandmaster ;-) and in the next game, well...
There is a small (but finite) probability for you to score any Elo rating in the elometer test, so having just one outlier like yours does not mean that the test is bad.


Why didn't Spassky play 26. g3 in game 5 of Fischer-Spassky (1972)?

I'd actually argue that the drawbacks of g3 are worse than Black getting a knight on f4. White permanently weakens the kingside light squares and blocks in his dark-squared bishop. Meanwhile, Black getting a knight on f4 is a bit unpleasant, but it's not necessarily a permanent problem.

Spassky probably thought that after 26...Nf4 27.Qc2, he was holding. He missed 27...Bxa4 of course, but if he had played 27.Qb1 instead, Komodo actually gives an equal evaluation. It's funner to play Black, but finding a plan to breakthrough is nontrivial.

After 26.g3 Nf6, Black is planning to play ...Qh5 and aggressively capitalize on White's weak light squares. If White stops this with 27.Qd1, Black has 27...Bg4.


Looking for a chess program that evaluates my playing and adapts its level to it

The Shredder app for IOS/Android has the following (optional) feature:

The program assigns to you a starting Elo.
When you play it, it adjusts its internal strength to match your Elo.
After the game, it adjusts your Elo based on the result.
The next game, it again adjusts its strength based on your Elo.

As you win more, it becomes more competitive until you reach a stage where your win ratio reaches around 50%.

About it being expensive - I recall paying about $5-10 for it, I guess it's up to you to decide whether that is worth the feature.

A few caveats from my experience:

The Elo calculated by Shredder is not a good estimate of your FIDE Elo. I stopped playing Shredder at around 1800, while my actual FIDE rating is less than 1600.
Shredder is better than most, but still not very good at simulating "human" play. This is especially noticeable at the lower strength settings - it will play like a GM for a few moves, then make a rather stupid tactical mistake, and then proceed to play like a GM.

If you are simply looking to have a bit of fun, then Shredder is great for that purpose, but if you are looking for a way to measure your playing strength as it would be against human opposition, it is simply not suitable for that - the only way you can measure how good you are against humans is to play humans.


Can a threefold repetition be claimed in a blitz game? If so, how?

It's hard, and I've never seen it done correctly, in the sense that it's the way I was taught it should go:

During slow games, once the players are not writing down their moves anymore because they are close to a game control, the arbiter should write down the moves as well to help with reconstructing the game after a flag falls (say to check if the 40th move is reached), or for claims like this. He can do so as well with blitz games, or appoint a temporary assistant to do so for him. It's just not usually done.

So you can stop the clocks and ask the arbiter to start recording moves, or appoint an assistant. In theory I think he should do that, and then when a threefold repetition occurs after that and you claim, the arbiter can check your claim using his notes.

But in practice, I think most arbiters will be too busy and too unfamiliar with these sort of rules to do that.

And of course, if you get the claim wrong, the opponent gets 3 minutes extra on the clock. Pretty hefty in blitz.


Fastest way to get both kings to the other side of the board?

It can be proven that 10 moves, or 20 plies, is the least possible.
[Title ""]
[FEN ""]

1. f3 f6 2. Kf2 Kf7 3. Kg3 Ke6 4. h3 h6 5. Kh4 Kf5 6. Kh5 Kf4 7. Kg6 Kg3 8. Rh2  Rh7 9. Kxh7 Kxh2 10. Kh8 Kh1

Here is the proof, listed in a logical order.
Observations Of Proof

Both kings must make at least seven moves to get to the other rank, so that's 14 plies off the bat.
Each side must move a pawn move to release a king, which costs 2 plies in further total.
Each side must move a piece to unguard a square for the other king, also costing 2 plies.
Finally, at least one more pawn move by both sides is required in order to let each king bypass the pawn structure, and that amounts to 2 plies.

In conclusion, 14+2+2+2=20 plies, so it is indeed the minimum possible.


Use lichess.org. When your opponent leaves game you can press button 'Claim draw/loss' there


In this case, because you probably cannot maintain it, and it will become weak. The principles of not making too many pawn moves, and developing your k-side and pieces quickly take precedence. It may also be too early to determine that d5 will be the most useful move.

   [Title ""]
[FEN ""]

 1. d4 Nf6 2. d5 e6 3. c4 (3. Nc3 Bb4 4. dxe6 fxe6) exd5 4. cxd5 Bb4+ 5. Nc3 (5. Bd2? Nxd5) 5... O-O {Black is already slightly ahead in development} 6. Nf3 d6 {White has had to artificially isolate the d-pawn, and it is weak. He also still had to develop the k-side, and could easily come under attack.}

P.S. To answer Trolly's question below: While the position is only slightly better for black, and hardly lost, his evaluation of the position is not really correct for several reasons. First, black is ahead in development right now, and white is surely going to need to make some concessions in order to finish developing in that position. Second, being ahead in development, there is little chance that white will be able to exploit any current weaknesses black may have anytime soon...you have to be able to get at a weakness to be able to attack it. If white does castle king-side, then the open rook-file is actually useful for black. Lastly, and this is very important, black may play d5 next move, and all of a sudden, d4 is a threat depending on what white's next move is. He may also get a big center after d5 with a subsequent e5. How exactly do you propose to castle queen-side with both Q and B wanting the d2 square? (give a sample line) because I really do not see it happening as easily as you think, and black may just throw in Bc3 if you have to capture with the b-pawn, and to prevent that is going to make white develop unnaturally.


Using the diagonal in perpetual queen checks?

As you said, this is a very general guideline, but looking back it has served me well in practical play.

Note that by "checking from the diagonals", the pattern I have seen is that the queen maintains a stable circuit on a diagonal but the checks themselves are usually horizontal or vertical.

I think it's because the checks from a diagonal allow the queen to keep the king in a box with only minimal pawn support (a single nearby pawn for either side will usually do it). Checks from a file or rank each allow the king to run across the board in one direction unless there's a pawn directly blocking his path.


Is the result in mini-chess known with perfect play?

The game is also known under the name pawns-only chess. There is a variation of this game called breakthrough that has more strategical depth by allowing the pawns to also move diagonally.

Since I had already implemented breakthrough, it was very straightforward to add an implementation of pawns-only chess to my Stockfish fork for fairy chess variants (actually I only had to define the rules in a simple structure, see the commit). I have run a single-threaded search for ~10 hours using 2GB of RAM, which yielded a mate score for all first moves, so the results should be reliable, although they are no strict mathematical proof, because Stockfish does forward pruning in its tree search.

The results of Stockfish's search state that the moves 1.b4, 1.c4, 1.f4, and 1.g4 are winning for white, whereas all other first moves are a win for black with perfect play. See the input and output below for details. Since the search was single-threaded and depth-limited, the results should be reproducible.

While writing this answer, I found that someone else independently had obtained the same results, see his chess stackexchange answer and github repository.

input:

setoption name hash value 2048
setoption name multipv value 16
setoption name UCI_Variant value pawnsonly
position startpos
go depth 40

output (truncated):

info depth 40 seldepth 38 multipv 1 score mate 18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv b2b4 g7g5 c2c4 f7f5 d2d4 g5g4 e2e3 g4g3 f2g3 e7e6 g3g4 f5g4 e3e4 d7d6 d4d5 e6d5 e4d5 h7h6 a2a4 g4g3 h2g3 h6h5 b4b5 b7b6 g3g4 h5h4 g4g5 h4h3 g2h3 a7a5 b5a6 c7c6 a6a7 c6d5 a7a8
info depth 40 seldepth 36 multipv 2 score mate 18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv g2g4 b7b5 f2f4 b5b4 e2e4 c7c5 d2d3 h7h6 a2a4 b4a3 b2a3 g7g6 h2h4 f7f6 f4f5 g6g5 h4h5 a7a6 c2c3 e7e5 f5e6 d7e6 d3d4 c5d4 c3d4 f6f5 e4f5 e6f5 g4f5 g5g4 f5f6 a6a5 f6f7 g4g3 f7f8
info depth 40 seldepth 40 multipv 3 score mate 20 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv f2f4 c7c5 e2e4 h7h5 c2c4 d7d6 g2g3 g7g6 f4f5 a7a6 a2a3 b7b5 b2b3 g6f5 e4f5 e7e6 c4b5 a6b5 f5e6 f7e6 h2h3 d6d5 g3g4 c5c4 b3c4 h5g4 h3g4 b5b4 a3b4 d5c4 g4g5 c4c3 d2c3 e6e5 g5g6 e5e4 g6g7 e4e3 g7g8
info depth 40 seldepth 40 multipv 4 score mate 20 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv c2c4 f7f5 d2d4 a7a5 f2f4 e7e6 b2b3 b7b6 c4c5 b6c5 d4c5 h7h6 h2h3 g7g5 g2g3 d7d6 c5d6 c7d6 f4g5 h6g5 a2a3 e6e5 b3b4 a5b4 a3b4 f5f4 g3f4 g5g4 h3g4 e5f4 b4b5 f4f3 e2f3 d6d5 b5b6 d5d4 b6b7 d4d3 b7b8
info depth 40 seldepth 39 multipv 5 score mate -19 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv b2b3 c7c5 c2c4 g7g5 a2a3 f7f5 b3b4 d7d6 h2h3 f5f4 g2g4 f4g3 f2g3 h7h5 g3g4 h5g4 h3g4 e7e6 e2e4 c5b4 a3b4 e6e5 d2d3 a7a6 c4c5 d6c5 b4c5 a6a5 c5c6 b7c6 d3d4 e5d4 e4e5 d4d3 e5e6 d3d2 e6e7 d2d1
info depth 40 seldepth 37 multipv 6 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv e2e3 b7b5 g2g4 e7e5 f2f4 e5f4 e3f4 c7c5 f4f5 d7d6 a2a3 d6d5 b2b3 h7h6 a3a4 b5b4 a4a5 a7a6 h2h3 g7g6 f5g6 f7g6 h3h4 c5c4 g4g5 h6h5 b3c4 d5c4 d2d3 c4d3 c2d3 b4b3 d3d4 b3b2 d4d5 b2b1
info depth 40 seldepth 37 multipv 7 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv a2a4 g7g5 f2f3 c7c5 a4a5 d7d5 e2e4 d5d4 e4e5 h7h5 g2g3 g5g4 f3f4 e7e6 f4f5 e6f5 d2d3 b7b5 a5b6 a7b6 c2c4 d4c3 b2c3 b6b5 d3d4 c5d4 c3d4 b5b4 e5e6 f7e6 d4d5 b4b3 d5e6 b3b2 h2h3 b2b1
info depth 40 seldepth 37 multipv 8 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv d2d3 g7g5 d3d4 b7b5 d4d5 a7a5 e2e3 h7h5 f2f4 g5f4 e3f4 h5h4 c2c3 a5a4 b2b3 a4b3 a2b3 e7e6 c3c4 b5b4 g2g4 h4g3 h2g3 f7f5 c4c5 e6d5 g3g4 f5g4 c5c6 d7c6 f4f5 g4g3 f5f6 g3g2 f6f7 g2g1
info depth 40 seldepth 37 multipv 9 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv h2h4 b7b5 g2g4 c7c5 c2c3 e7e5 f2f3 d7d6 d2d3 d6d5 e2e3 c5c4 d3d4 e5d4 e3d4 f7f5 g4f5 h7h5 f3f4 a7a6 b2b4 c4b3 a2b3 a6a5 f5f6 g7f6 c3c4 d5c4 b3c4 b5c4 f4f5 c4c3 d4d5 c3c2 d5d6 c2c1
info depth 40 seldepth 37 multipv 10 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv f2f3 g7g5 c2c4 f7f5 e2e3 e7e5 b2b4 f5f4 e3f4 e5f4 c4c5 d7d6 d2d4 d6c5 d4c5 c7c6 a2a3 a7a6 a3a4 h7h6 g2g4 f4g3 h2g3 h6h5 b4b5 h5h4 g3h4 g5h4 b5a6 b7a6 f3f4 h4h3 f4f5 h3h2 a4a5 h2h1
info depth 40 seldepth 37 multipv 11 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv g2g3 g7g5 g3g4 c7c5 a2a4 d7d5 a4a5 e7e6 b2b3 e6e5 c2c3 e5e4 d2d3 e4d3 e2d3 d5d4 c3d4 c5d4 b3b4 a7a6 h2h3 f7f6 f2f3 h7h6 b4b5 a6b5 h3h4 g5h4 a5a6 b7a6 f3f4 h4h3 f4f5 h3h2 g4g5 h6g5
info depth 40 seldepth 39 multipv 12 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv h2h3 b7b5 h3h4 f7f5 a2a3 c7c5 b2b3 d7d5 c2c3 c5c4 b3c4 d5c4 h4h5 e7e5 d2d3 c4d3 e2d3 a7a5 g2g3 a5a4 f2f3 h7h6 g3g4 f5f4 g4g5 h6g5 h5h6 g7h6 d3d4 e5e4 f3e4 f4f3 d4d5 f3f2 e4e5 f2f1
info depth 40 seldepth 37 multipv 13 score mate -18 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv d2d4 b7b5 h2h3 g7g5 e2e3 h7h5 e3e4 f7f6 d4d5 a7a5 c2c3 h5h4 b2b3 b5b4 c3c4 c7c6 d5c6 d7c6 c4c5 e7e6 g2g4 h4g3 f2g3 f6f5 e4f5 e6f5 h3h4 g5h4 g3h4 f5f4 h4h5 f4f3 h5h6 f3f2 a2a4 f2f1
info depth 40 seldepth 35 multipv 14 score mate -17 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv e2e4 g7g5 d2d4 b7b5 f2f3 h7h5 c2c3 f7f6 b2b3 e7e6 d4d5 e6d5 e4d5 f6f5 g2g3 g5g4 f3f4 a7a5 a2a3 a5a4 d5d6 c7d6 b3a4 b5a4 c3c4 d6d5 c4c5 d5d4 c5c6 d7c6 h2h3 g4h3 g3g4 h5g4
info depth 40 seldepth 35 multipv 15 score mate -17 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv c2c3 b7b5 e2e4 g7g5 d2d4 a7a5 f2f3 c7c6 g2g3 d7d6 d4d5 c6d5 e4d5 e7e6 h2h4 g5h4 d5e6 f7e6 g3h4 h7h5 b2b3 b5b4 c3b4 a5b4 f3f4 d6d5 f4f5 e6f5 a2a3 b4a3 b3b4 a3a2 b4b5 a2a1
info depth 40 seldepth 35 multipv 16 score mate -17 nodes 52290435219 nps 1359031 hashfull 1000 tbhits 0 time 38476253 pv a2a3 b7b5 e2e4 g7g5 d2d3 a7a5 d3d4 h7h5 f2f3 f7f6 e4e5 f6e5 d4e5 a5a4 g2g3 e7e6 h2h3 h5h4 g3h4 g5h4 b2b4 a4b3 c2b3 c7c5 a3a4 b5a4 b3a4 c5c4 a4a5 c4c3 a5a6 c3c2 f3f4 c2c1


Can I become a GM by playing 100 games per day without studying books, strategy, etc?

Let me play devil's advocate here (since everyone seems to take the negative position) and say yes, you absolutely can.

But, and this is a big but (no pun intended) the games you play have to be "good" games, and it will not be enough to simply play them, but rigorous analysis must also be done on each game that is played.

The absolute truth of the matter is that any student, with enough motivation, a cheap computer with a decent processor, some (free) chess software and either a lot of talent or a lot of time, can become an IM or even GM. This is something not many players will admit, because it seems to subvert all the chess-related purchases they might have made.

In the past, it was necessary to hire a tutor, or read books and other chess literature, to keep up-to-date on opening theory and to learn chess. Today, with the advent of powerful chess engines and game databases, much of this is obsolete. Furthermore, I would argue that chess books are not only outdated, but outright inefficient when compared to the alternatives. These are bold claims, so let me try and support them with a plan of action which is bereft of any chess literature and focuses only on games.

The Plan

Don't play 100 short games a day, this is a waste of time. Play 1 long game (90 minutes or more) against a moderately strong computer engine and spend the rest of the time doing analysis
You will lose pretty much every game you play (if the computer is set to its highest level) but you must not get discouraged or change your style of play to beat the computer (i.e don't play closed positions solely for the reason that computers are bad with them). This is where motivation and discipline will determine whether you really benefit from this method.
In every game, focus on a single thing and try to improve it. Initially the biggest problem might be gross blunders, hence you should do a blunder check on every move you play to prevent such blunders from occurring.
You should try to create a thinking algorithm, a step-by-step process or checklist which helps you to make decisions over-the-board and then use this algorithm for every move (until it becomes habitual and automatic). Steps might include things like the blunder-check above, or deciding whether the position is tactical (requires intensive calculation) or positional (requires sound planning and positional understanding). This is the only thing where it might be faster (not necessarily better) to read up on, instead of building it yourself, since efficient thinking systems already exist that were created by very successful players (Capablanca, Nimzovitch, Tal etc.).
Analysis of your games should be done to figure out weaknesses or lapses in understanding. The easiest way to do this is to look at positions where you spent the most amount of time. A computer must be used to keep yourself objective and grounded in the concrete, but is used only to check your analysis, not to replace it. (Most computer engines have the option to analyze your annotations and almost all give a point score for every move, take advantage of these options).
Play in tournaments and OTB games, record them, and analyze them the same as your other games. These games are more valuable, because you can actually win them once in a while and because they are games outside of a controlled environment (i.e not in the comfort of your home).
You will undoubtedly improve the most by focusing on your own games, but for a change of pace you might want to analyze a collection of games by a strong GM or favorite player. You should do this by playing guess-the-move from the winning side, making annotations for moves you guess (correctly or incorrectly). Then check the game with a computer engine (you'd be surprised with how many mistakes you find, both in your own analysis and in the moves of the GM's). You can also use these games to figure out the thinking algorithms of the masters.

If you actually stick to the above recommendations, I really think you'd make significant progress. Much more so than if you spend an equivalent amount of time reading a book. The reason is because passively reading something is very inefficient, compared to actively learning through difficult training games. Why is reading/chess literature still popular? Mostly because it gives a false sense of accomplishment and because its enjoyable. Ask yourself if the last chess book you read gave you a significant boost to your rating or chess understanding. Ask yourself how much you actually remember from the book, whether the concepts or games or annotations, and how much of it has actually influenced your OTB play.

The method above is not merely my own conjecture but is inspired by the training system developed by Botvinnik (there is a portion I left out, concerning physical exercise, but I think that's self-evident), who emphasized long-time-control training games and thorough analysis for chess improvement. The emphasis on thinking algorithims comes from the research done by de Groot.

Ultimately the final verdict, is yes, you can improve in chess through just games. But few have the dedication, discipline and motivation to do so.


If you really must, because your friend bet a wager that he can beat you as black in this position, here are the imbalances, concrete and possible, that you must look out for (as white):
[FEN ""]

1.e4 d5 2. exd5 Qxd5 3. Nc3 Qd8

Black's open d-file
Active LSB
Kingside pawn majority

Still, this is not without its weaknesses:

A delay in development. White can safely continue with d4, Be3, Qd2, O-O-O.

Black's reduced control of the squares on the e-file. Castle long and prompt to push his f-pawn somehow, followed by a minority attack g2-g4 (or g2-g4-g5).

Black's reduced control of the squares on the c-file. If black castles long, or the situation somehow else warrants it, break open the c-file, create an outpost on the c4-c5 square, and move a knight, bishop, or rook to this square where b7-b6 or b7-b5 has to happen. Now you'll have a new, but weakened structure to attack.
Black will play to nullify white's knights with ...Bg4 (if Nf3), ...e6, ...Bc5, Ne7, and O-O, finally obtaining a solid position. If white castles short, black can launch a minority attack, creating holes which his knights can then infiltrate. He can place pressure on the d-pawn by restricting its advance, playing c7-c6, ...Rd8, and ...Nd5. If white plays c4, then the d-pawn has become weakened and serves as a target.


Stockfish, Houdini and Komodo (many other engines too) can all be configured like what you said. This is known as Contempt. In Komodo, the name is Drawscore (same thing). If you give enough negative value to the option, the engine will not push for a win even it sees it.

http://support.stockfishchess.org/kb/advanced-topics/engine-parameters


What are some ideas for black in the Ruy Lopez when white plays an early d3?

I have found some ideas for you from an online source. I hope that this helps you!

Quote: “All this being said, there is some downside to playing d3 one move earlier -- there always is. Seeing as the idea of playing 6.d3 following 5...Be7 is to have black commit to developing their bishop to that square, playing d3 a move earlier with 5.d3 allows black to play differently and more advantageously. This is done by black playing d6 (protecting the e5 pawn) followed by g6 and Bg7, which is a useful and common maneuver found in many Ruy Lopez lines. Black here is able to develop their bishop to g7 immediately, and white can't punish this with an early break in the center with d4 (a la the Fianchetto/Smyslov Variation of the Ruy Lopez with 3...g6), as it comes with a loss of tempo (time) because the d3 pawn has already moved. Therefore, black is thought to equalize rather easily if they conduct this early Bg7 maneuver against 5.d3 (occurring roughly 20% of the time according to databases), as black essentially reaches a Deferred Steinitz or Russian Defense type of position with an extra tempo. You can think of 5.0-0 as a very useful waiting move in relation to the 6.d3 variation, in that it waits for black to commit their bishop so that white may potentially hang on to an advantage somewhat longer.” -Source: https://hubpages.com/games-hobbies/Chess-Openings-The-Ruy-Lopez-with-6-d3


Plans for White and Black in the Queen's Gambit Accepted

I'm not an expert on this line, but one idea from "Study chess with Matthew Sadler" stuck in my mind: To play against the b7-bishop with f3 and e4. So that might be an objective for white. For black this is probably harder to archive, because the Nc3 is ready to jump into d5.

But this Nc3 instead of Nd2 gives black a different target: The square c4. Say after 14…Rc8 15.Nd4 Ne5 makes some sense, to jump into c4 and possibly acquire the bishop pair. Though after 16.Nb3 this doesn't yet work tactically, because of 16…Nc4 17.Bxc4 Rxc4 18.Na5 Rc7 19.Nxb5 …

So maybe 14…Rc8 15.Nd4 Nb6 is better, because on b6 the knight will be more stable. Then 16. Nb3 and possibly Nfd5 with the idea to exchange the Nc3 and go Bb7-d5-c4.

This was a bit of a stream of consciousness, but I'll try to sum up:

Playing f3 and e4 to blunt the bishop b7 is an idea.
The squares c5,a5 and c4,a4 are targets for the pieces. Especially the knights can be very annoying if they reach such a square.
There is always the idea of playing a4/a5 to try and liquidate the whole queenside, especially if there is still a rook on the a-file.
This might look like a very calm position, but with so many pieces still on the board, you should definitely look out for tactical possibilities.
If you don't find anything better to do, you can move your king closer to the centre: It is always possible, that some mass exchanges leave you in an endgame, where the king centralisation will be key.


Because he is losing the Rh8, and at that level, that is an EASY win. It is also worse than that as mate is coming in a few moves. Even without the almost immediate mate, being down a pawn and an exchange is a lot of material.

By the way, although black did not take it, white did offer a queen sac on move 24.Qg7, but had it been taken, a new queen would have appeared next move.

 [FEN "2q4r/2rbkp2/4pQpP/pp4P1/4P3/5P2/PPPR4/2K4R b - - 0 1"]

 1... Kf8 2. Qxh8+ Ke7 3. Qf6+ Kf8 4. h7 {And mate after a couple of spite checks on c2.}

Here is the full game:

 [Event "EU-ch rapid"]
 [Site "Tallinn"]
 [Date "2019.12.05"]
 [Round "1"]
 [White "Aizenberg, Benny"]
 [Black "Guseinov, Gadir"]
 [Result "1-0"]
 [ECO "B77"]
 [WhiteElo "1995"]
 [BlackElo "2691"]
 [PlyCount "55"]
 [EventDate "2019.12.05"]
 [EventType "swiss"]
 [EventRounds "13"]
 [EventCountry "EST"]
 [FEN ""]

 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 g6 5. Be3 Nf6 6. Nc3 Bg7 7. Bc4 O-O 8. Bb3 d6 9. f3 Bd7 10. Qd2 Nxd4 11. Bxd4 b5 12. h4 a5 13. Nd5 Nxd5 14. Bxg7 Kxg7 15. Bxd5 Rc8 16. h5 Rh8 17. O-O-O Qb6 18. g4 e6 19. h6+ Kf8 20. Bb7 Qxb7 21. Qxd6+ Ke8 22. Qd4 Rg8 23. Rd2 Rc7 24. Qg7 Rf8 25. Qxh7 Ke7 26. Qg7 Qc8 27. g5 Rh8 28. Qf6+ 1-0


Who has the advantage at this point in the game?

In this position, the material imbalance pretty much tells the whole story, as a queen and two pawns against two knights is, barring significant positional compensation, an overwhelming material advantage. And in this case, the non-material positional considerations only serve to emphasize Black's advantage: the white king is exposed, and his pieces are not well coordinated (one knight pinned, and the remaining forces at risk of becoming overloaded trying to protect one another). The upshot is that White is powerless to prevent Black from further increasing her (already winning) material advantage, liquidating to a situation in which White has nothing left to play for or with. Resignation wouldn't be unreasonable for White.

To illustrate, if Black has the move (the OP doesn't say whose move it is), then 1...Bxc4 already yields 2.bxc4 Rxe3+ 3.Bxe3 Qxe3+, when Black has a queen and two pawns for a rook, and can win at her leisure. But even if White has the move, he is so tied up in knots that he can't stop that operation (or something similar). For example:

[FEN "2k5/1pp2p2/p5p1/3b4/2NBq2P/1PK1N1r1/P7/3R4 w - - 0 1"]

1.Re1
    ( 1.Rd3 Bxc4 2.bxc4 f5 3.Kd2 f4 )
1...Bxc4 2.bxc4 f5 *

Black can continue to pick up material with her queen in the open field, and White won't even have an army with which to dream of mounting an improbably comeback.


What are the worst blunders ever committed in a world championship match (final)?

By far, the biggest blunder in all world championship is absolutely 32.Bb4?? played by Chigorin in the 1892 match. He threw away the win and the match, landed himself to mate in 2.

https://en.wikipedia.org/wiki/World_Chess_Championship_1892
A piece up, Chigorin should have won after 32. Rxb7 (32...Rxd5? 33. Nf4 forks the black rooks).[1] Instead the game and match ended suddenly when Chigorin blundered with 32. Bb4?? Rxh2+ White resigns, as Black will mate on the next move.[1][3]


If you're familiar with LaTeX (or if you're willing to learn it, which in my opinion is time well spent), there are some user-created packages which exist just for that. These are very easy to download (e.g. via with the MiKTeX Package Manager) and use.

To my knowledge, the most extensive and well-documented of these packages for creating chessboards is chessboard. As you can see in the documentation, it's highly flexible. As for chess fonts (i.e. being able to write moves with the symbol for the piece rather than the letter for the piece), there's the package chessfss. There are other packages too if ever these aren't to your liking, for example chess-problem-diagrams.


Who are the strongest non-professional GMs?

Up until recently, that title would have gone to Teimour Radjabov without question in my mind. Since April of 2015 until last month, he has only played 149 games. That is not many for a top-flight GM over four and a half years. That said, he just won the right to play in the Candidate's, so he may becoming more active again.

Quite a number of old GMs were musicians and engineers. GM Mark Taimanov was also famous as top concert pianist in the Soviet Union. Mikhail Botvinnik was famous for being an electrical engineer and computer scientist while also being the world champion at the same time. Dr. Ruben Fine was a Doctor of psychology. GM Helmut Pfleger of Germany is an MD.

GM Lars Bo Hansen is 2560, and is an Assistant Professor of Sport Management and Business Strategy at Florida Institute of Technology in Melbourne, Florida.

As stated by Ian Bush, Luke McShane is considered the strongest with an outside full-time job, but I am not sure I would give him the title "of strongest non-professional GM" based solely on that as he plays a fair amount, and has played 182 games in the same time frame as I listed for Radjabov. Based on that, and the 100-point difference, I still have to go with Radjabov.

Here is a cool list of chess players, who have doctorates.


Only being able to move and not capture while in check

Below is for regular chess. I don't know about any chess variant which would have a rule like you describe.

If you are in check you have to deal with it somehow, i.e. after your move you should not be in check anymore. If there is no move which achieves this, it is check-mate.

There are at most three different ways to get out of check:

move the king out of check
capture the piece which attacks your king
put a piece in-between the piece which attacks your king and your king (this can only work if a bishop, rook or queen attacks your king)

A simple example:

White is in check by the rook on h7. There are three possible moves for white: Kg1 (see "1"), Bxh7 ("2"), Nh3 (see "3").

As a side note, you cannot castle out of check.