Is it poor form to win a drawn position on time? I was playing a 3-minute game, my opponent had around 15 seconds to my ~50 seconds when he managed to cancel out the last pawns to make it so we each had a king and a rook. I let his time run out and he accused me of poor form. Should that have been a draw?

This is opinion based and therefore not a great fit for the Stack Exchange format, but here are my thoughts anyway.

The lower the time limit, the more acceptable it is from a sportsmanship view. In standard long time controls, this is really poor form. In 1-minute ("bullet"), anything goes, including this. The reasoning is that in these really fast forms of chess, the clock is as much a part of the game as the board is (so 15 vs 50 seconds is actually a type of winning position), whereas in slow chess the clock is more of a necessary concession to tournament organizers, not something equal games should be decided on.

I'm in doubt about 3 minute chess. It's very fast, but I'm not sure on which side of the fence it is, that'll be different from person to person.

Personally I always offer a draw when this position arises, but then I only play for fun, not for big bucks.

K + B vs K + B with bishops on opposite colors is even worse, it's hardly even possible to make a blunder in that. At least with rooks you have to watch out for skewers.


How to practice tactics correctly? When it comes to tactics training what is the best approach to optimize results? I've recently started only doing really hard puzzles, the only immediate change is it obviously take me a lot longer and end up maybe doing around 10-20 per day. Is it quality or quantity that's more important? Also as a side question I keep hearing that playing blindfold chess is bad for you for some reason? Can someone explain why I keep hearing that?

I'm assuming your aim in practicing tactics is to improve your game performance.
In that case, I would recommend you treat each problem not as a puzzle, but as a real game situation, because your goal is to be able to spot tactics OTB, without knowing whether or not a tactical shot exists or not.

Thus, you should apply the thinking process you would use in a real game to the puzzle, and just try to play the move you would in a real game.

This means that you would, after a quick evaluation of the initial position, look for (1) Forcing moves, checks/caps/threats, (2) logical, positionally sound options that increase your activity/decrease opponent's activity. Then, you should calculate and evaluate these candidate moves one by one, and determine which one is the best. This is how you would play in a real game, and thus your tactical training should be like this.

If you can't spot the tactic (get the problem wrong), then you know that something is wrong with your thinking process, and you can correct it immediately. For example, if you spotted all the appropriate candidate moves, but, after calculation/evaluation, didn't find a winner, and thus settled for a "positional" move, then you know that there's an issue in your calculation; maybe you didn't remember to find all candidate moves at every move, and thus missed something. Or perhaps you couldn't visualize a long sequence, and now you know you have to get better at this.

This is assuming you know how to improve every aspect of your thinking process. There are many free online resources, particularly youtube, that tell you how to train to improve certain things.

I think that 10-20 difficult puzzles is plenty, as long as you apply your thinking process to each, and remember to diagnose/improve your thinking process at the end of each puzzle. Also, remember that in a real game, you have around 3 minutes per move. In critical situations, you may use more, but try not to use more than x minutes for a move, if you not spend more than x minutes on the position in a game.

Also, playing blindfold chess is not bad. Blindfold chess is one way to improve your visualization skills, which is crucial for calculation.

I am a USCF expert rated player.


Why and how do great chess players become "crazy"? I know that this question may be for a more psychology-focus forum, and "great" is an understatement for players such as Fischer; yet, I want to know your opinion on this question. Is it intelligence? Is it pressure? Or is it the game itself? Whatever is the ultimate answer, I wonder if the grand gift or talent has a big backlash, or even at a lower level of play, does playing game become harmful then?

edit: Maybe I should rephrase my question a little bit. Why and how do some great chess players become mentally ill, and why and how do others stay mentally stable? I would like to hear more about the other side of the discussion.

King's Gambit: A Son, A Father, and the World's Most Dangerous Game is about this. The age-old question is:
Does chess make you mentally ill or are mentally ill people attracted to chess?

Chess has the highest suicide rate of any sport by a long-shot.
Many chess world champions were mentally ill.

There's a whole bunch of other supporting facts about chess being linked to insanity, but I'd have to re-read the book to recall all of them.
All the insanely brilliant people in my life have some form of mental illness. I consider myself extremely fortunate to know these people. They're genius about things I can't begin to understand. There's two bipolar geniuses and two Aspergers geniuses. I know three of the four love chess.
And then there's my 135 IQ friend who's bipolar, her boyfriend from back in the day who was a genius and schizophrenic, my straight A friend who's depressed and maybe a little autistic, my aspergers 130+ IQ friend, my nerdy (aka autistic/aspergers traits) friend with depression who's 138.
So basically every intelligent person I can name has some sort of "disorder." Remember that by definition, being intelligent isn't normal. Who's to say one is the correct or incorrect way to think? Just because the majority of people think at a normal intelligence doesn't necessarily mean that's the right way to think. That's just how almost everyone thinks, so they only diagnose the exceptional people. Maybe you could argue that having a normal level of intelligence should be its own mental disorder.
For example, normal people don't get intelligent questions. Look at some questions on here written by geniuses and you'll see they're immediately flagged and closed. People rationalize it after the fact. It's unfocused, or too specific, or not a real question, or misguided, or all over the place, or off topic, or whatever. The kind of thinking that seems obvious to the intelligent person needs to be justified to normal people. Remember that as a society we villainize intelligence. Nobody normal is interested in big ideas. That's weird. All they care about is whether or not this is going to make their life more comfortable. And I'm not really sure why we were put on this Earth, but I'm pretty darn sure it wasn't to make ourselves comfortable.
See where I'm going with this?
My Calc professor left his copy of that book on my desk the day I went in to take my final exam for his class. He loves chess and mathematics. I'd visit him in his office after my class ended to say hi. We'd talk about intellectual giants and infinity and chess. Sometimes you can get caught on a problem, and start thinking about it forever. And eventually it'll drive you crazy. That's what happened to a lot of these mathematicians. Maybe these chess guys just got too absorbed in their own world. But it takes a tremendous mind to be capable of creating a world.
See where I'm going with this?


Simultaneously managing attack and defense I am an amateur chess player. I have the knowledge of pawn structure, development of the pieces and control of the center in the opening. After that my midgame rationale is attacking the weak pieces, and if I am under an attack, focus on defense. This has failed to work among much stronger opponents of late. How would I change my rationale so that I can manage defense and attack at the same time?

Defense isn't something that one does; it is not a tactic. Instead, defense happens when one has ceded the initiative to the opponent. One spends moves patching holes versus attacking the opponent's weaknesses.

(Of course at some point "tactics" and "retaining the initiative" blur. Some fine attacking moves also defend, and some defensive moves free other pieces to attack. It can be a maelstrom when it comes to specifics.)

So consider reading on tempo and initiative.


Short castle in Trompowsky In recent 1st Match between Maguns & Karjakin, started with Trompowsky. How can Karjakin prefer catsle even g file is open ( g × f6 at 3rd move ). Whats idea behind it?

A few thoughts:

Leaving the king in the centre or long castle are not attractive either with all the open lines and pinned knight on c6
The g file is open but it is not easy for white to make use of it. White has exchanged its bishop which would have had a good square on h6. Also black's pawns on e6 and f6 cover important squares that could be occupied by white knights.
The centre is open and if white concentrates forces on the king side, black will very quickly push through on the queen side and in the centre.
It is an opening and has been analysed by humans and computers and found to be OK.


Is there a Unicode-compatible alternative to PGN? One of the problems with PGN is that it requires ASCII, while names of players often contain non-ASCII characters. (And of course, many names are not written in the Latin alphabet ...)

The background to this question is the rendering of non-ASCII characters in Arena 3.5.1 (on Windows 7), as in the image below. The names for white and black are Mittelsträß, Jürg and 王, 玥, respectively. Arena reads the UTF-8-encoded file as if it were encoded as Windows Codepage 1252. Editors such as Notepad++, SublimeText and JEdit identify the file as UTF-8 (which is the default encoding of all my plain text files, anyway).

Here's an example PGN for testing:

[Event "Office Armageddon"]
[Site "Böblingen GER"]
[Date "??.??.??"]
[Round "?"]
[White "Mittelsträß, Jürg"]
[Black "王, 玥"]
[Result "*"]
[SetUp "1"]
[Mode "OTB"]
[Termination "unterminated"]

1. d2-d4 d7-d5 2. e2-e3 c7-c5 3. Bf1-b5+ Bc8-d7 4. a2-a4 Ng8-f6 5. d4xc5 e7-e5 6. b2-b4 Nb8-c6 7. Ng1-f3 Qd8-c7 8. Nb1-c3 a7-a6 9.  *

(SCID assumes a system encoding if a PGN is encoded in UTF-8 without a byte order mark (BOM), but the BOM makes no difference in Areana 3.5.1.)

So I'd like to know if there is a Unicode-compatible alternative (ideally UTF-8) that is supported by some chess programs. (If not, PGN needs an overhaul.)

https://sourceforge.net/p/pgn4web/wiki/PGN_Support/

if you read that, you will notice:

 in order for pgn4web to display those characters correctly, the PGN file should be saved in unicode UTF-8 format.

you can save PGN as UTF-8... Just open notepad > Save As... > Encoding and select UTF-8. and you can then add the appropriate player names! I've tested this, and it works with Arena Chess and a few others...

Hope this solves your problem. ~CSS


Resources on the caveman Caro-Kann The caveman Caro-Kann goes:

[fen ""]
1. e4 c6 2. d4 d5 3.e5 Bf5 4. h4 h5 5. Bg5!?

Any anotated games, resourses, books, etc, are apreciated.

There is some analysis at the Kenilworthian blog. See http://www.kenilworthchessclub.org/games/java/2007/caro-adv-h4.htm
http://www.kenilworthchessclub.org/games/java/2011/cavewoman.htm
http://www.kenilworthchessclub.org/games/java/2013/complete-caveman.htm
http://kenilworthian.blogspot.co.uk/2013/03/the-complete-caveman-caro-kann_20.html

Download for the PGN:
http://www.rci.rutgers.edu/~goeller/kenilworth-pgn/complete-caveman.pgn

and also analysis by Dennis Monokroussos here:
http://www.thechessmind.net/storage/chess-posts/anand_shirov_leon2011_day3.htm


How to create your own opening book for your own chess engine? I am currently working on a chess engine in Java. I am using the minimax algorithm with alpha-beta pruning to select the best move. However, it is inefficient to use the algorithm for selecting opening moves.

So here is my question for people who have experience with making their own engines:

How do you make your own opening book? Do you create your own database to store different openings and their successive variations? Or is their a general database that one can connect to and extract moves?

I would gladly appreciate any help from anyone who has experience or knowledge on this.

It may depend a little on what your code can access, but either way you should read Ed Schröder's pages on this topic.  Schröder was the author of the Rebel Chess software until his retirement about a decade ago.  In the '90s Rebel was the strongest consumer/commercial chess software and the first such to beat a GM (Anand).  Since retiring he turned Rebel into ProDeo and released it for free on his website.

Start with this introduction, though you should already know all that, then have a look at this more in depth explanation.  Then check this page for details on adding Rebel/ProDeo books to any engine (will require compiling C code for each platform you want your engine to be able to work).  You should be able to add to the books from PGN records before compiling them.

EDIT: Not quite sure why this was voted down, but probably the mention of C when the OP states Java.  I should mention that most chess processing software is in C or C++ because it provides better processing capabilities; it compiles to assembly language or machine code, unlike Java, which requires the JVM to run and that makes Java less efficient.  Yes, it is possible to compile Java into machine code, but hardly anyone ever does it because then it is no longer platform independent (such as it is).  So the OP will be running into the C hurdle no matter what.

Beyond that, these sites on the chess programming wiki on opening books and opening suites may be of use.  You'll find a bunch of Ed Scröder's stuff there because he is one of the pioneers who made the shift from hardware electronic chess systems (e.g. Mephisto) to personal computing software.  With the added bonus that now he's giving his software and, more importantly, his knowledge away to whoever wants it.  If that's really not enough to immerse one's self in the subject then nothing is.


Chess Tutorials for Beginners I am a chess beginner but I have been playing the game for many years without being very serious about it. I would like to improve a bit now though but I am having difficulty with many of the sites....I like the sites that provide problems to be solved but the main issue I have with them is when you make a wrong move it says...wrong move!! I would like it to be a bit more specific than that and tell me why it was a wrong move as sometimes it looks like the right move to me!!! (That's why I'm still a beginner of course....) But I think it would be extremely helpful to know this. Is there any sites out there that provide that sort of service?

It's hard to find resources like that. Beyond the basics or how to move, you can look at

Beginner Study Plan - I'd recommend having a look at this guide so you know what to study. Then I would advise you look at Yasser Seirawan's Winning Chess Series. For beginners, look at

Play Winning Chess

Then when you progress, you can look at

Winning Chess Tactics

and later you can look at

Winning Chess Endgames
Winning Chess Openings

These books are easy to read and provide lots of examples with very clear explanations from one of the best chess authors out there.

You should definitely learn all the tactical motifs that exist. By knowing what they are, you can try to find them in real games, and over time they will start to become second nature. I recommend Attacking Chess by Josh Waitzkin, which is a really good book for beginners learning tactical puzzles. You can probably find a PDF of the book online if you want, but I'd advise buying it.

Tactical Motifs - This website has tens of thousands of tactical puzzles and will show you the solution if you get the puzzle wrong. Each puzzle has a tag which lets you know what tactical motif was used. For a beginner, you should know forks, pins, skewers, double check, back-rank mate and x-rays. There are plenty more tactical ideas, but these will help most.


Is any chess software specifically for forced mates? Is any chess software specifically for forced mates?

In particular, such software can only prune the search tree when it can prove

that the the move doesn't affect the existence of length of a forced mate.

Joseph Ellis on talkchess has a modified Stockfish for mate solving.

Updates:

1) Sync with latest SF.
2) Move to full hash key.
3) Increase max depth to 250.
4) Improve mate detection.

https://dl.dropboxusercontent.com/u/1145468/MateFinder.7z

The archive includes the source and two very basic windows compiles.

http://talkchess.com/forum/viewtopic.php?t=58597&highlight=mate+solver

The Github URL: https://github.com/jhellis3/Stockfish/tree/mate_finder

I never downloaded the archive and have no idea how good it is. I think it might worth a try as Joseph seemed to know what he was doing.


Software To Create Chess Videos Is there any free software to create chess videos? I see some nice videos on chess.com and on Youtube. The way arrows are drawn on the board, highlighting squares or pieces are really wonderful features.

Programs like ChessBase, ChessPad, Scid vs. PC, and Lucas Chess all let you highlight squares & draw arrows on the board. You can then just record what you're doing using regular screen recording software like the excellent oCam.

Edit: I've created a video showing how to use Lucas Chess to create instructional chess videos. View it here. (YouTube)


Why am I getting different behaviour between using stockfish as a child node process and a CLI called process? Copied this question from stackoverflow. Not 100% sure it belongs here but we'll see...

I am building a web interface for the stockfish chess engine using Node, and I noticed that the behaviour of the exact same commands behaves differently.

Here are the UCI commands I use when calling stockfish from the command line:

position fen rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
go movetime 15000

The engine then responds as expected: Does analysis for 15 seconds while outputting every step on stdout, and ends with a suggestion in the following format:

bestmove e2e4 ponder e7e6

Here is the code that makes the same call as a node js child process:

app.get('/next_move/:fen', (req, res) => {
    const stockfish = spawn('bin/stockfish');
    stockfish.stdin.write(`position fen ${req.params.fen}\ngo movetime 15000`);
    console.info(`Sending UCI command to stockfish: position fen ${req.params.fen}\ngo movetime 15000`);
    stockfish.stdin.end();

    stockfish.stdout.on('error', (error)=>{
        console.error(`${error}`);
        res.status(500).send('Internal server error');
        stockfish.kill();
    });

    stockfish.stdout.on('message', (data)=>{
        console.log(`Message: ${data}`);
    });

    stockfish.stdout.on('data', (data) =>{
        let output = data.toString();
        // Ignore the first line in stdout
        if (output.substring(0, 9) === 'Stockfish') {
            return;
        }
        console.info(`Stockfish output: ${output}`);
        if (output.substring(0, 8) === 'bestmove') {
            res.json({'bestMove': output.substring(8).trim()});
        } else {
            res.status(400).send('Bad FEN string');
        }
        stockfish.kill();
    });
});

After I make this code run via web, get a result almost instantly, and also get a different output from stockfish:

bestmove a2a3

Why is this happening? Is this related to Nodejs or to Stockfish?

It was me who suggested you to come here because you'd need to understand what's happening. The guys on Stackoverflow wouldn't have the knolwedge to answer you.

Firstly, this is definitely your fault since Stockfish wouldn't give you a2a3 unless you have screwed up something. But why a2a3? That's because Stockfish always try to move a pawn before anything else. The way how the bitboard is encoded, it'd start its search from a1 to h1, then a2 to h2, a3 to h3 etc. The a2 white pawn is the first pawn it sees, so it tries to move it.

Now we've established it's your fault, however, it's not possible for us to determine the cause because we don't have your source code. But I can give you some hints, you'll need to experiment yourself.

You have killed the standard input too early. I don't quite understand why you would do stockfish.stdin.end();. Stockfish assumes the standard input/output works, always works.
You have failed to setup the bitboard. I'm confident you'd get the error unless you let Stockfish to setup it's internal data structure. Have you done it? The code for doing it should be in the main() function, did you run it? You can't just run the UCI loop directly, it wouldn't work.
How did you host the engine? Did you host it in the same address space as the server? Note that the engine assumes it's in a different address space because this is how a desktop GUI would work.
Print out everything you send to Stockfish and everything you receive from the engine. Don't assume your commands would work, print everything to a text file. Run the commands in a command line. Stockfish could give you nonsense if one of your commands is not right. You'll have to verify it by trying yourself, don't assume anything.
If you still can't figure out what's happening. Put a breakpoint in the UCI loop and follow it. There has to be something, a condition that makes your search terminate immediately. Don't be afraid, you should be able to debug it yourself if you follow the code step-by-step.
Have you done ucinewgame?

Most likely it's (2), a common mistake in chess programming. If you don't run the setup code correctly, the engine wouldn't be able to run the nega-max algorithm. No nega-max => nothing to search => simply return you the first pawn move.


Balancing chess and work I started chess 2 years ago at 500 ELO and have climbed up to 1900 ELO (chess.co) recently. I have fallen deeply in love with the game and have made it a life goal to achieve eventually a mastery title.
Unfortunately, I started chess very late (20 years old), an age where one usually is in university and starts or has started working. Very soon I will have to move to my apartment, work full time, cook food, etc. I fear I will not have enough time as I currently do to dedicate my self sufficiently to chess; a lot of time is required to improve in chess. I was wondering how does one balance chess serious improvement and work/life responsibilities ?
In conjunction with this question, what would you consider an optimal training time regime? Is 1 hour a day sufficient time to gradually improve, or will that be pointless?

20 years old is not that late to start.  Any amount of time spent can help improve or maintain skills.  Consider how much time you would like to spend and commit to it.  Adjust to ensure you are enjoying your chess time.  Easy to improve when having fun. An hour a day is fine to start.
How you spend you time is also important.  There is much good advice on this site, for example this
You will not get a title playing on chess.com.  Consider playing in tournaments that lead to titles.  Probably your rating will be different then chess.com so that will give you a better idea how close you are to your goal.
I learned to play when I was 7, but in my teens I did not have anyone better than me to play so I could not improve.  Once I started university it was easy to find folks better than me and I started playing and studying chess much more.  Most of my chess improvement was during university.


Casual chess meet up in London UK I’m a (predominantly) online chess player.  My rating is roughly FIDE 1800-1900. I’m travelling to the UK next week for work.
Is there a place or club or cafe in the inner or outer London area where I can go and find like-minded strangers for a friendly casual game?

I was in London two weeks ago, and attended a causal chess club in the central London.

http://casualchess.org/

It was a quiet pub, and the environment was good. What made it special was that it had a number of woman chess players. I tested my skills against those females.

As a FIDE 1800-1900 player, you will find yourself beating everybody there.


Touch-move when move is illegal but opponent's piece can be captured by another piece This is the scenario: I pick up my Knight to capture my opponent's Bishop (touching the Bishop). I then realise my Knight was pinned to my King in the first place, so moving it would be illegal. However, I have already touched my opponent's Bishop with my Knight. Since I have touched my opponent's Bishop, would I have to capture the Bishop with another piece of mine (in this case my Queen can legally capture the Bishop instead), or am I allowed to just move any other piece entirely? Reference in FIDE Rules is Article 4.3.3 but it still seems it doesn't explain this scenario well enough.

Article 4.3.2 clarifies this -

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

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

In the scenario you describe you touch your knight and your opponent's bishop with the intention of capturing the bishop with your knight. Moving the knight is illegal hence you may not capture the bishop with the knight. However capturing the bishop with some other piece, your queen, is legal. Therefore you must capture the bishop with that piece.


London System as White: exchange of the light-squared bishops The following is a position that frequently arises in my games when I play the London System as White:

  [FEN ""]

1. d4 d5 2. Bf4 Nf6 3. e3 Bf5

At this point I am unable to place my light-squared Bishop in its best square (d3) without allowing an exchange of Bishops which does not seem favorable to me as the White light squared Bishop is better than the Black (all White pawns in the center occupying black squares - especially after c3 which will also be played at some point).

Yet, when browsing the database at lichess.com the most frequent continution is 4. Bd3 which invites exactly such an exchange. I' ve toyed with ideas of Nf3 followed by Nh4 in an attempt to drive off the Black Bishop (or exchange him with my Knight) but without much success.

How should White approach this Bishop exchange? Should it be avoided and, if not, how does the London System plans (for White) change after the light squared Bishop is lost?

The best way to deal with the "copycat" is to switch to the Queen's Gambit with c4 with the idea of following up at the right time with Qb3 to take advantage of the weakness on b7.


Can any opening get outdated? Chess getting played since long years with evolutionary advancements. In this process few openings or variations may get outdated. Can it happen so?

The game of chess depends upon outwitting your opponent. Part of the toolbox used by the top players is changing the openings so that their opponents find themselves surprised and unprepared for the new position. This also results in opening variations that are discarded because a flaw has been found.

Openings also go in and out of fashion, for the same reason. The Scotch Opening, for example, first became popular when it was played in a major correspondence chess match between the London and Edinburgh Chess Clubs from 1824-1828, at the recommendation of the Scottish player, John Cochrane.*

Here's a summary of how often it was used in the years that followed, as a percentage of all Double King Pawn games (1.e4 e5) that were played in that period:

Period   Period  Scotch
Begin    End     Opening %
1824     1900,    7.5%
1900     1950     3.3%
1950     1989     5.4%
1990     2000    10.4%

The jump in the last period has been attributed to Garry Kasparov's surprising Anatoly Karpov with it during their match in the 35th World Championship in 1990. In addition, for the 16 years after that, from 1990 through 2005, Garry Kasparov had a score of 17-8-0 with it (17 wins, 8 draws, no losses). This drew attention to the opening again.  It has maintained its popularity in the years since that match.

However, the King's Gambit has not gone through the same increase in popularity:

1824     1900,   16.5%
1900     1950     9.4%
1950     1989     5.4%
1990     2000     2.9%

From this data, you might think that the reason the King's Gambit is unpopular is because the results that White achieves with this opening are disappointing.

But that hypothesis can be disproven: In that last period, 1990-2000, White scored 56% with this opening, with only 18% draws. This is a substantially higher rate of wins than in many other openings.

However, at the highest levels of play (players over 2400 ELO), White scores only 51% with this opening! This is very poor performance, when compared with a 55% win rate in all Double KP openings.  So, because they don't get good enough results with it, it's unpopular at the highest level of play. Only 2.2% of all double KP games involve the King's Gambit at 2400+ ELO.

This suggests that players at lower levels are following fashion set by the highest level players, not the actual results they can achieve in practice at their own level.

*The Scotch Game Explained, Gary Lane, Batsford Chess 2005, p.5


An offline alternative to lichess.org's online analysis engine Lichess.org has probably the best chess analysis interface. But, the problem it works only online.

Whereas, Stockfish the engine behind the analysis is downloadable, the interface is not.

I am looking for an analysis software (preferably open source and free) that uses traditional engines and can provide data such as number of blunders, mistakes, inaccuracies etc,. And, preferably with graphs and statistics like lichess.org.

The reason for open source is that so it can be compiled across several operating systems. And, most importantly, can be modified to suit individual needs.

I will strongly recommend SCID. Its open source and very feature rich.


Why does Stockfish prefer White here? My analysis of the position:

Materially, black is a pawn up.
White's rooks and bishop are active.
White has potential counterplay on Black's Kingside but I think it can be defended by the move Ng6.
Black's queen is active.

According to my analysis, the position is quite equal and I don't find any reasonable justification for stockfish's score.

Can you please explain why does stockfish prefer white here?

The main feature in this position is the lack of defenses around black's king. After Rg1 followed by improving the bishop, either h5 or c4 to pressure f7, you are effectively attacking with an extra rook.

Some sample attacks are:

1) Although a beginner's attacking formation, aligning a queen-bishop battery--by d4, Qd3, Bd1-c2, threatens a simple mate on h7.

2) After an exchange sacrifice on g6, the weakness on the white squares are easily exploited after the bishop gets to c4.

3) After the Knight reaches f5, via Nf1-e3, the pressure on g7 and especially h6 is difficult to protect.

The knight on g6 is the king's best protector, but, mainly due to it being on a white square, it is easily removed, and then black's kingside becomes exposed.


How can I remember Silman's imbalances? I can never remember Silman's imbalances when it comes time for a tournament. I can remember them any other time when I'm not all stressed out. Is there any way that I can?

At the moment you are trying to remember the imbalances using declarative memory:

  Declarative memory (“knowing what”) is memory of facts and events.

Whereas you need to have the imbalances in procedural memory:

  Procedural memory is a part of the long-term memory that is responsible for knowing how to do things, also known as motor skills.

So you need to internalise the imbalances by practicing, for example using the The Reassess Your Chess Workbook by I.M. Jeremy Silman.


What to do after losing a game? What to do after losing a game?

I think that this question is on everyones' minds after a loss. I am guessing that everyone has their own way of coping with a loss. The best way to cope with a loss can turn out to vary from person to person. Yet, I think that it should be possible to find some sort of "best practice" procedure to draw wisdom from a loss and cope with it in a productive manner. Most chess players I know, including myself, feel terrible after a loss. One of the first negative thoughts that arises is

  What is the point? I trained and competed so much and I still lost!

Today, I know that there are (at least) three ways of losing a game.

Become completely outplayed with virtually no counterplay.
Blunder (e.g. during time trouble).
Enter a position with chances for both sides, do your best and still lose.

It is clear that whatever level of skill you have, you can still lose. So what to do afterwards? Is there a best practice?

The best practice would be to thoroughly analyze the game and also your thought process before, during and after the game. Besides, if after sincere hard efforts you still lose, it's important to have an attitude like this -

  “I haven't failed, I've found 10,000 ways that don't work” - Thomas
  Edison

In chess, that would mean -

  I haven't failed, I have discovered that this
  strategy/opening/tactic/etc. doesn't work.

In my personal experience, you often learn more from the games you lose than from the games you win. So use that to your advantage. Analyze the game thoroughly (of course with the help of an engine) and see where you went wrong. Also, identify faulty patterns of thinking during the game. For example -

  "this position was objectively equal, but during the game I thought I
  was worse and so I got demotivated and played badly".

Gary Kasparov suggested the following after winning (but I suppose it applies all the more after losing) -

  "Even the game we won always contained mistakes; inaccuracies. It's
  inevitable. I can hardly find one brilliant game with no mistakes."

  "If we won, it is most likely because our opponent made the last
  mistake. But, he made the last mistake and he is definitely analyzing
  the game; he'll find what we did wrong in the previous stage of the
  game. So what is important is to find it first."

I found some other interesting quotes on this page. Some of the more interesting quotes are -

  Losing can persuade you to change what doesn't need to be changed, and
  winning can convince you everything is fine even if you are on the
  brink of disaster.  -  Garry Kasparov

  Don't be afraid of losing, be afraid of playing a game and not
  learning something. - Dan Heisman

  I prefer to lose a really good game than to win a bad one.  -  David
  Levy

  Setbacks and losses are both inevitable and essential if you're going
  to improve and become a good, even great, competitor. The art is in
  avoiding catastrophic losses in the key battles.  -  Garry Kasparov

  You may learn much more from a game you lose than from a game you win.
  You will have to lose hundreds of games before becoming a good player.
  -  Jose Capablanca

  Most players ... do not like losing, and consider defeat as something
  shameful. This is a wrong attitude. Those who wish to perfect
  themselves must regard their losses as lessons and learn from them
  what sorts of things to avoid in the future.  -  Jose Capablanca


Comparison of tactics trainers I've noticed that the nature of the tactics differ from one website to another. For instance, on lichess.org/training (the website which I train tactics the most on), I have noticed that tactics always present (at my rating level, at least) with the following features:

The opponent has just blundered, and the position we are playing is now winning (but was not before the blunder). There are no puzzles where one must hang on to keep the position equal, or play for a draw;
There is always only one correct sequence of moves, i.e. each move is markedly better (according to Stockfish) than all of its alternatives. There are no problems where one must find the most accurate win, with other variations still winning;
The computer will always respond the best moves, not the most natural or most challenging ones, or the ones that were actually played in the game. For instance, say the tactic involves a mate threat, and that the opponent can choose between going down a full queen immediately (with no immediate mate), or trying escape with the king, with the latter alternative leading to forced mate in 7 (the line we should actually be calculating). Then the computer will lose its queen and the tactic will be over much sooner than if it had tried to save the position.

It is easy to imagine why these features make the problem of identifying tactics from analysed games more tractable, but from the perspective of learning the game they are not ideal: 1. results in defensive play being neglected and 2., 3. make the puzzles less representative of real play. I found this old blog post on how tactics are generated on lichess, but I believe things have changed a lot since then and I think it's no longer relevant (I was not able to find more recent posts, and have not attempted to look at their code).
I have noticed that on chess.com/puzzles 3. (and possibly 1.) do not occur, but I'm not sure since I train rarely there. I actually prefer the problems on lichess, since they look (at least at the starting position) a little more realistic. I'm also aware of a few other websites, like chesstempo (where I believe multiple moves are allowed).
This is my main question: Can anyone provide a comprehensive comparison of the different tactics trainers available, in terms of the above and other characteristics? How are these differences explained in terms of the algorithms that mine and create tactics? How can I best train various aspects of tactical play, which may not all be accessible on one website?

The tactics trainers cannot be compared to each other.
You need to compare them to a specific person as everybody has different needs and preferences.
That said, all the ones I have seen are done poorly from an educational perspective which would most effectively help you improve as fast and as far as  you could.


Can I place my rooks upside down at the beginning of the game? Numerous times I’ve read that it’s illegal to use an upside down rook to represent a promoted queen because “it’s still a rook”. Does that imply that I can begin the game with my rooks upside down? They are still rooks; they are still centred on their squares. Sorry for semi-frivolous question but I would enjoy to read the authoritative answer. Thanks so much!
EDIT: Or maybe one could use an upside down rook to indicate the castling right is gone on that side, if the rook has wandered away from its starting square and then returned :D Practical! Almost sensible! :)

The FIDE laws of chess say nothing about upside-down rooks. However, starting with upside-down rooks is silly and if your opponent complains that it is annoying, I would expect the claim to be upheld.

  11.5 It is forbidden to distract or annoy the opponent in any manner whatsoever.

https://handbook.fide.com/chapter/E012018

The proper way of dealing with a missing queen (or any other piece) needed for promotion is to stop the clock and call the arbiter for assistance. However, the upside-down rook tradition comes from less formal settings, or maybe lower-budget situations where no arbiters with spare pieces in their pockets are close at hand.

It is interesting to note that the USCF rules explicitly allow the use of upside-down rooks for promotion:

  8F7. Promoted piece not available. If the desired piece is not available to replace a promoted pawn, the player may stop both clocks in order to locate that piece and place it on the board. A player who cannot quickly find such a piece may request the assistance of the director. It is common practice, however, to play using an upside-down rook for a second queen. In the absence of the player’s announcement to the contrary, an upside-down rook shall be considered a queen.

Just, Tim. US Chess Federation’s: Official Rules of Chess, 7th Edition.


If I accidentally knock over a rook with my elbow while reaching for another piece, do I have to move the rook? According to the official FIDE rules for otb games, does the above description warrant the touch move rule?

No.

The relevant part in FIDE's Laws of Chess is Article 4.3 which contains the word deliberately.

  4.3 Except as provided in Article 4.2, if the player having the move
      deliberately touches on the chessboard:

  a. one or more of his own pieces, he must move the first piece touched which can be moved

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

  c. one piece of each colour, he must capture the opponent’s piece with his piece or, if this is illegal, move or capture the first
      piece touched which 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.

The situation you describe once happened to a team mate of mine. The opponent wanted him to move the touched piece according to the rule, but the arbiter explained it had to be deliberate.


Does this trap have a name? I can across this trap playing a bullet game and I wonder if it has a name:

    [FEN ""]

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Nc3 Bc5 5.Nd5 Nxd5 6.Bxd5 Nd4 7. Ng5 O-O 8.Qh5 Nxc2+ 9.Kf1 h6 10.Nxf7 Kh7 11.Nxd8 Rxf2+

And now black has a checkmate in 3.

The pattern starting from Nxf7 does not correspond to any known (opening) trap. It's to be expected as this does not really qualify as a trap for the following reasons:

The path up to the critical position 10.Nxf7 has major flaws, e.g. white is hanging a full knight on move 7.Ng5 (7...Qxg5), so objectively, white is already lost before any trap setup is reached. Therefore, this move order does not really belong to a branch of a known opening (here the Four Knights game: Italian var).
Opening traps usually occur when one side is baited/tempted towards a known losing variation, such as the Légal Trap. Sometimes the side attempting to set up a trap might have to make a non-optimal, nearly dubious move to force the desired variation, but (at least for most known traps) if the opponent spots the trap and plays a refutation the game remains about equal.

However, in your example, assuming black is indeed setting up a trap, white can [*] simply play 11.d4 instead of falling for 11.Nxd8, and white's completely winning as both dxc5 and Bxh6 are threatened and they cannot be simultaneously parried, therefore, black is lost and if anything, all this has been nothing but a last attempted tactical bait in an otherwise completely lost position.

[*]: other than the fact that white can simply play 9.Kd1 instead of Kf1 and be completely winning having also side-stepped black's combination along the f-file.


"Dead-draw" endgame lost? Are there examples of games between notable players where "dead-draw" endgames
 were lost ?

For examples : Both players had three connected pawns on the f-g-h-file (or
 a-b-c file) without free pawns and the king were near the pawns and material
 was level.

Such positions are generally considered to be "dead-draw".

This game between Ponomariov and Carlsen was quite a sensation in 2010. Especially because there is no single outrageous blunder - Ponomariov is just outplayed very systematically. Alas, one has to keep in mind that it was a rapid game.

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. cxd5 Nxd5 5. e4 Nxc3 6. bxc3
Bg7 7. Bc4 c5 8. Ne2 Nc6 9. Be3 O-O 10. O-O Qc7 11. Rb1 Rd8
12. Bf4 Be5 13. Bxe5 Nxe5 14. Bb3 Ng4 15. Ng3 Qf4 16. h3 Nf6
17. e5 Nd5 18. Ne2 Qe4 19. Ng3 Qf4 20. dxc5 Be6 21. Qd4 b6
22. Ne2 Qf5 23. cxb6 Nxb6 24. Qf4 Rac8 25. Qxf5 Bxf5 26. Rbd1
Bd3 27. Rfe1 a5 28. Nf4 Bc4 29. Rxd8 Rxd8 30. Re4 Bxb3 31. axb3 Rd1
32. Kh2 Rb1 33. c4 Rxb3 34. c5 Nd7 35. c6 Nb6 36. Rd4 Rc3
37. Nd5 Nxd5 38. Rxd5 Rxc6 39. Rxa5 Rc4 40. Kg3 e6 41. f4 h6
42. Kf3 Rc3 43. Kf2 g5 44. fxg5 hxg5
45. Ra4 Kg7 46. Rg4 Kh6 47. g3 Kh5 48. Ra4 Kg6 49. Ra5 Rd3
50. h4 gxh4 51. gxh4 Rd7 52. Ke3 Rb7 53. Kf4 Rb4 54. Kg3 Kf5
55. Ra7 Rg4 56. Kf3 Rg7 57. Ra5 Rg1 58. Rb5 Ra1 59. Rc5 Ra3
60. Kf2 Ke4 61. h5 Ra8 62. Kg3 Kf5 63. Kh4 Ra4 64. Kg3 Rg4
65. Kf3 Rf4 66. Kg3 Kg5 67. h6 Rg4 68. Kf3 Rh4 69. Rc7 Kg6
70. Rc8 Rxh6 71. Kg4 Rh1 72. Rg8 Kh7 73. Ra8 Rf1 74. Ra2 Kg6
75. Rg2 Rf5 76. Re2 Kg7 77. Kg3 Kf8 78. Re4 Ke7 79. Kg4 Kd7
80. Rd4 Kc6 81. Rd6 Kc7 82. Rd1 Rxe5 83. Rf1 f5 84. Kg5 Kd6
85. Kf6 Re4 86. Rd1 Kc5 87. Rd8 f4 88. Kg5 e5 89. Kg4 Re3
90. Rd1 Kc4 91. Rd2 f3 92. Kg3 e4 93. Kf2 Rd3 94. Ra2 Kd4
95. Ra4 Ke5 96. Kg3 Rd2 97. Ra5 Kd4 98. Ra4 Ke3 99. Ra3 Ke2
100. Kf4 f2 0-1


Suggest a line for a player who does not want to be dragged into the Sicilian I am a very bad Sicilian player and I am easily played out of book in the Sicilian defense. I need a line that would prevent my opponents fom going into the Sicilian defense. I have tried c4, but sometimes it transposes into a Sicilian with the Maroczy bind. I know d4 is good, but are there any other suggestions I could play?

You could transpose to the Botvinnik English System:

[FEN ""]

1. e4 c5 2. c4

Because it is a system opening, you usually put your pieces on the same squares regardless of what Black does. For example:

[FEN ""]

1. e4 c5 2. c4 Nc6 3. Nc3 g6 4. g3 Bg7 5. Bg2 Nf6 6. Nge2 O-O 7. O-O d6 8. d3

The usual piece placements are:

Fianchettoed kingside castle
Knights on c3 and e2
Queen on d2 and bishop on e3
A rook off the a1-h8 diagonal, e.g. on b1

Evaluating this opening we see that:

It's a system opening, so it is easy to learn. But it doesn't give the best chances to win
The Botvinnik Triangle, pawns on c4, d3 and e4, allow White to play on any sector of the board. For example: breaking with d4, attacking with f4 or gaining space with b4
White has a hole on d4, which might be quite tender

See also the YouTube video Chess Opening for White: Botvinnik-English System against the Sicilian Defence.


Chess coaching and coaches training different players What does coaching actually mean in chess?

In relation to that, how is it possible for a chess player to coach two different players? Do the trainees share their work, or does the coach work on different areas of the game with each player, and in that way avoid any "moral conflicts"?

Two of the most notable examples would be:

-Peter Heine Nielsen, who was coaching Anand for ten years (Wiki), before switching to his main WCC rival Carlsen in 2013 (although he was also helping Carlsen before 2013);

-Vladimir Chuchelov, who coached both Fabiano Caruana and Anish Giri (I am not sure whether he even coached them simultaneously at some point).

On the other hand, Gelfand stated in 2012 that he refused an offer from Kasparov to help him in his match against Anand, since Kasparov was helping Anand in his WC match against Topalov in 2010.

I cannot imagine coaches deliberately trying to keep secret some of the work they have previously done (it seems too artificial). Also, revealing all the secrets of the player they previously worked with, does not seem to me as "morally sound". So, what is the deal then?

Well first lets start with the most simple answer... Chess is not such a simple sport that if taught to multiple people will result in the same thing. Even if what you learned was exactly the same.

If you are interested in getting into more detail then please read on :)

Chess coaching in a sense is just you sharing what you know... That's all there is to it, you tell your students how to think as chess players but that does not necessarily mean they WILL think like that.

Chess coaches simply hone, and help their students master their skills, they give them the knowledge needed (and of course more) but that doesn't mean it will always result in the same thing.

If I were to give a real life example, this would be the most simple and true to chess.

You can have a machine that takes metal as a material and it constructs a bike, however if you go to another machine and give it the exact same material that doesn't mean it will also produce a bike, it might give you a car! Who knows...

-----------------------------------------

^ That was the answer, here is some extra stuff if you are interested in more.

Over time in the history of chess, many players like Mikhail Tal, Boby Fischer, Alekhine and so on... All of them had their own unique play style that is remembered until today. However no one can deny the fact that ALL of them had a lot of shared knowledge, they knew the same things yet even so, they played differently.

Chess is simply a beautiful war on a small 64 square battlefield... Even if you both know the same things and same tactics, you still have your own unique plans.

And now I am done :P Sorry for the long post, but hopefully I helped.


Why is my theoretical knowledge is not coming to any use? For the last few months, I have been reading "How To Reassess Your Chess (I expected at least this book to work), "Simple Chess," "The Art Of Attack," some ending book, "Modern Chess Strategy," etc. I was not practicing at all, and now I have started to play against the Fritz computer, which has a rating of 1450. I am losing most of the time in the opening and blundering in the middlegame sometimes. I have not read any opening books as I have heard that only after a 2000 rating you should memorize openings (I know the basic setups). I just don't understand. People say doing lots of puzzle increases tactical awareness and reduces blunders. But I am still making mistakes with 2-3 move blunders. What did I do wrong? I have only played about 120 chess games sp far.

Perhaps so called theoretical knowledge has no real use.
You should ask why your rating/ability has not been improving.
At only 120 games you are a total beginner. I presume you meant online games.  If those were actual OTB tournament games then you need to switch to checkers.
You need to play less and study more effectively.  Just playing games will not help you very much and is a very slow way to improve.
You MUST learn two openings COLD no matter your rating.  One for white and one for black.
You will need to do effective tactics training.  Most online trainers are not done to help you learn efficiently.  There are some, not a lot, books that are better.
You need to study GM tournament games.  Play over every game by every player.  You will get a feel for what good moves are and which are not so good.
Best if you do not play all the games  then  at least play all the games for W/B that used  your preferred opening.   None of them did?  Maybe you need to pick a better opening.
Learn endgames!   If you get that far you will be surprised how many high rated players are clueless about what to do.  If you know them then you will beat a lot of players with lower ratings if you get to the endgame.  Did I mention to learn openings and play GM games to get a feel for good moves?
After that you need to move to strategy and positional play so you will keep improving. Tactics will help you beat the slash and burn attack at all cost kiddies, but playing good players who do not do that will require positional understanding.


How would FIDE handle a player with ADHD in tournaments? I recently stumbled upon Why is coffee provided during big chess events when it contains a banned substance? and learned that amphetamines are banned by FIDE.
How would FIDE handle a player with ADHD who is rightfully prescribed amphetamines?

How would FIDE handle a player with ADHD who is rightfully prescribed
amphetamines?

FIDE handles this in the same way as all Olympic sports handle such things. Anybody who follows such sports (particularly cycling) will be familiar with "Therapeutic Use Exemptions" or TUEs.
They are covered in the FIDE Anti Doping Rules:

4.4 Therapeutic Use Exemptions (“TUEs”)
4.4.1 The presence of a Prohibited Substance or its Metabolites or Markers, and/or the Use or Attempted Use, Possession or FIDE Anti-Doping Rules 14 Administration or Attempted Administration of a Prohibited Substance or Prohibited Method, shall not be considered an anti-doping rule violation if it is consistent with the provisions of a TUE granted in accordance with the International Standard for Therapeutic Use Exemptions.

FIDE provides a standard Therapeutic Use Exemptions (TUE) Application Form which can be downloaded from their site, filled in, signed, and submitted.


Why is taking notes that encourage oneself illegal in chess? In Round 9 in the US Chess Championship 2015 Men, Wesley So (2794) was forfeited by the arbiter in his game against Akobian (2622) since So took notes that were not chess-related but contained "general encouragement and advice to himself".

The game be seen here.

I think that is absurd. I think a chess player can write whatever they want as long as it does not offend anyone.

I can't claim to know for sure what was going through the minds of the authors of the FIDE Laws of Chess, but I think the intent is to ensure that the players use only their unaided intellect to play the game.  Players aren't allowed to make/use written notes during the game.  At all.  About anything (chess-related or not).  If they're allowed to make notes about things other than chess, or the game in progress, you then put an arbiter in the position of having to determine if such notes are chess-related or not.  It would certainly be possible for a player determined to cheat to come up with a system in advance to disguise the nature of what they're writing.

It's worth pointing out that So wasn't forfeited for making the notes - he was forfeited because of rule 11.7 - "Persistent refusal by a player to comply with the Laws of Chess shall be penalised by loss of the game".  He had been warned twice before during the tournament that he wasn't permitted to make written notes, and the second time was warned that a third infraction would result in a forfeit.


Why taking the bishop with queen is better here? [FEN "rnbq1rk1/pp1B1p1p/5bp1/2pPp3/8/8/PPPNQPPP/R1B2RK1 b - - 0 1"]

The engine doesn't want me to take the bishop with the bishop, but to instead use the queen and I don't understand. What difference does it make?

Your queen then attacks the undefended white d-pawn.
Also, white is threatening Ne4 (attacking the black squared bishop), and after e.g. Bg7, taking on c5. If black took with the bishop, this would fork the white squared bishop on d7 and the undefended pawn on b7. If black took with the queen, black could simply take the d5 pawn and defend the b7 pawn while attacking the knight.


I played my first (rapid) tournament recently and I wanted to calculate my ELO According to FIDE regulations I should calculate the average of my opponents and just plug it here: https://ratings.fide.com/calculator_rp.phtml.
I scored 5/9 but a couple of players didn't have rapid rating so I don't know if I should count those players as 0 points of ELO or just calculate the avg without them.
Also I don't understand the point 8.21 of the handbook:

  8.2 Determining the Rating 'Ru' in a given event of a previously unrated player.

  8.21 If an unrated player scores zero in his first event his score is disregarded.
    First determine the average rating of his competition 'Rc'.

    (a) In a Swiss or Team tournament: this is simply the average rating of his opponents.

    (b) The results of both rated and unrated players in a round-robin tournament are taken into account. For unrated players, the average
    rating of the competition 'Rc' is also the tournament average 'Ra'
    determined as follows:
        (i) Determine the average rating of the rated players 'Rar'.
        (ii) Determine p for each of the rated players against all their opponents.
        Then determine dp for each of these players.
        Then determine the average of these dp = 'dpa'.
        (iii) 'n' is the number of opponents.
        Ra = Rar - dpa x n/(n+1)

  8.22 If he scores 50%, then Ru = Ra

  8.23 If he scores more than 50%, then Ru = Ra + 20 for each half point scored over 50%

  8.24 If he scores less than 50% in a Swiss or team tournament: Ru = Ra + dp

  8.25 If he scores less than 50% in a round-robin: Ru = Ra + dp x n/(n+1)

Should I calculate my 'Ru' using the average of the rating of my opponents, of the whole tournament or is it more complicated than that?

Thanks in advance.

Here are the games and opponents, I have only the 9 games I talked about so it might help: https://ratings.fide.com/chess_statistics.phtml?event2=&event=1669320

OK, so the tournament was the Rattenberger Schnellschach-Open 2019 Tiroler Einzelmeisterschaft im Schnellschach It was a Swiss tournament. Here are your results from the tournament.

One of your opponents, Karl-Heinz Staudacher, has no rating. You should exclude your result against him altogether.

One of your opponents, Manuel Keßler, has a standard rating but no rapid rating. In the listing his standard rating has been used for pairing purposes and I believe this will also be used in rating calculations.

That means that you scored 4/8 against rated opposition. Accordingly (8.21a and 8.22) your rating will just be the average of those 8 opponents' ratings = 1885.5 which will be rounded up for display as 1886. If you play more FIDE rated rapid tournaments in June then the results from these tournaments will also be used in your calculations.

  I don't understand the point 8.21 of the handbook

This first says that if you score 0 in your first tournament then all your results in that tournament are excluded from the calculations. This is usually a good thing because it means that results which would give you a low rating (or no rating at all if it works out at below 1000) are not used.

Coaches of weak players playing their first tournament and losing their first few games often advise the player to either lose the last game or two or to pull out of the tournament to take advantage of this rule.

The rest is just giving the rules for calculating rating in case of round robin and Swiss. Your tournament was Swiss so you should use those rules.


Adding time to game played with chess engine Are there any chess engines out there that will allow me to add arbitrary amounts of time to their clocks as the game progresses? I am interested in experimenting with two engines playing each other with me manually (or programatically) giving each bonus time throughout the game according to an algorithm I've developed.

I don't know for sure on this, but if you go on Lichess, there is an option to add 15 seconds to your opponent's clock in live chess, I do not know with computer chess. I usually use Chess.com's live chess VS a bot.


How do I prepare against someone if I have a database of his games ChessTempo offers a service to see all the games of your opponent. The thing is, it also shows what the opponents played. So if I see 100 times e4 was played, 60 of the times might be because of the opponent. How can I only see the moves made by the person I'm going to face?

First of all, I don't think that chesstempo or other sites are actually good for preparation. I just took a look and saw that there are only 9 moves of each game displayed. If you are taking chess seriously, it's better to get the chessbase or at least fritz. They are more user friendly and statistics are better.

Regarding your question's title. Preparation is a complicated process. It depends mostly on time you are willing to spend on it. If you got tons of time and the game you are preparing to is very important, you should totally x-ray your opponent looking at all the games. Probably with someone more experienced in order to advise you a little bit.

Anyway, some basic stuff:

Check what openings your oponent play and what is his win rate/draw rate/lose rate, you know why.
What is your standard answer to his opening? Do you feel comfortable with it? What's your W/D/L ratio there? Are there game of YOURS in database? Keep in mind, your oponent might be prepared aswell!
Are there any games/variations that your oponent has a big lose rate? How well do you understand those positions? Do you know any similar structures that you could drag him into?

So in simple words: spot the weakness and exploit, that's it.


Pawn Promotion to Queen I have my rook on the 8th rank.  My pawn is directly behind it.  I want to move diagonal with my pawn to promote it to a queen.  Can I move diagonal to reach the 8th rank and promote my pawn?

You may do so only if the pawn is capturing one of the opponent's pieces; that is the only way a pawn ever moves diagonally. So here you can do what you describe:

[fen "3Rn3/k2P4/8/8/8/K7/8/8 w - - 0 1"]

1.dxe8=Q

But if you're talking about a situation like the following, then no, the pawn cannot move as you described:

[fen "3R4/k2P4/8/8/8/K7/8/8 w - - 0 1"]


Is this the correct flow of a chess game? I am trying to program a chess game as a challenge to myself, however, I am unsure if I have all the moves correct to play a legal game (not any advanced moves, that would be a challenge for another day).

I have created a flowchart/pictorial and text version to depict the flow of the game and the available moves.

The area with a blue background is the main game loop.
The area in dark purple are all the possible chess moves.

if there is any part that doesn't make sense or needs clarification please don't hesitate to ask and I will try my best to reword it.

Game Loop (start move)

is in checkmate?

yes

lose game

no

threefold repetition?

yes

stalemate

no

pawn moved in past 75 moves?

yes

stalemate

no

has captured in past 75 moves?

yes

stalemate

no

Get all available pieces for current player

iterate all pieces

check pawn moves
check knight moves
check bishop moves
check castle moves
check queen moves
check king moves

change player

Chess Moves

Pawn Move

was last move a pawn?

yes

was it a double move?

yes

choice

capture en passant
other choice

no

other choice

no

is first move?

yes

check diagonals for enemy?

yes

choice

would kill enemy put in check?

yes

check other pieces to move

no

kill enemy

is on opposite side of board?

yes

promote

other choice

no

forward 1 empty?

yes

forward 2 empty?

yes

choice

would forward 1 put in check?

no

forward 1

is on opposite side of board?

yes

promote

yes

other move

would forward 2 put in check?

no

forward 2

is on opposite side of board?

yes

promote

yes

other move

no

would forward 1 put in check?

forward 1

is on opposite side of board?

yes

promote

no

check other pieces to move

no

check diagonals for enemy?

yes

choice

would kill put in check?

yes

other choice

no

kill enemy

is on opposite side of board?

yes

promote

other choice

no

forward 1 empty?

yes

forward 1

is on opposite side of board?

yes

promote

no

check other pieces to move

Knight Move

forward 2 left  1 empty?

forward 2 right 1 empty?

right 2 up 1 empty?

right 2 down 1 empty?

would move/kill put in check?

yes

if checked all moves check next piece

no

move to available spot

back 2 left 1 empty?

back 2 right 1 empty?

left 2 up down 1 empty?

left 2 down 1 empty?

Bishop Move

check all diagonal spaces stopping if there is a piece in its way

does move put in check?

yes

check other moves else check other pieces

no

move to available spot

Queen Move

same as bishop except all cardinal and intercardinal directions.

Castle Move

choice

check all cardinal spaces stopping if there is a piece in its way

does move put in check?

yes

check other moves else check other choice

no

move to available spot

has moved?

yes

check other pieces

no

has king moved?

yes

check other pieces

no

is queenside castle?

yes

is in check?

yes

check other pieces

no

king 1 to queenside castle in check?

yes

check other pieces

no

king 2 to queenside castle in check?

yes

check other pieces

no

is adjacent spot towards king free?

yes

would put in check?

yes

check other pieces

no

move king 2 towards  queenside castle,  jump castle over king

no

check other pieces

no

is in check?

yes

check other pieces

no

king 1 to kingside castle in check?

yes

check other pieces

no

king 2 to kingsidecastle in check?

yes

check other pieces

no

move king 2 towards kingside castle,  jump castle over king

King Move

choice

has moved?

yes

can castle? (Note: for the sake of non duplication see arrow)

no

check other pieces

check all 1 move in cardinal and intercardinal spaces

does move put in check?

yes

check other moves else check other choice

no

move to available spot

I don't think it's going to work. Consider this fragment:

You don't "kill enemy" just because your pawn can do the capture. What if your pawn capture exposes your queen behind? What if your pawn capture leads to back-rank mate?

Furthermore, you're not making yourself clear how to choose between moves. Your flowchart implies your program would be making legal pawn moves before considering anything else. This won't work.

You'll have to do searching, something like alpha-beta/nega-max. Your flowchart is way too simple for a reasonable chess engine, if that's your goal.

There won't be any "challenge" from your flowchart. I estimate the program would play no better than a random player. However, if your aim is just to make something that can play a legal chess game; your flowchart is reasonable. It's also a nice mini-project for practising programming.


Is there any transposition available in between QGA and other openings? I'm a chess player with ELO 1600. Now I'm trying to learn transpositions in chess. QGA is my favorite opening as white. But most of the time black chooses Queen's Gambit Declined. So now I'm trying to get to get QGA by transposition. Chess is all about positions. But I just want to know:

Are there any transpositions available in between QGA and other openings?

One transposition white can try is from the French Exchange variation (if you know your opponent plays the French).

[FEN ""]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. c4 dxc4 (4... Nf6) 5. Bxc4

It transposes to the variation 1. d4 d5 2. c4 dxc4 3. e3 e5 4. Bxc4 exd4 5. exd4 from this question.

In the French move order, clever black players won't take the pawn on c4 already on move 4, but will wait until white plays Be2. If white then later regains a pawn with Bxc4, the bishop will have lost a tempo.


How to avoid the French in the Alekhine, Scandinavian Variation? After 1. e4 Nf6 2. Nc3 d5 3. e5 Ne4 4. Nce2 Nc5, black intends to undermine White's center with ...Ncd7 and ...c5. The e5-e6 pawn sac is not available at the moment.
What is a good way to keep the opening sharp, or steer (or develop) the position into those reached by 4. ...f6 (the main line here runs 5. d3 Ng5 6. Bxg5 fxg5 7. h4)?

The 4...Nc5 line clearly differs from the mainline you've given, since the knight on c5 will not be traded on g5 with black's pawn structure getting somewhat compromised. However it seems like the immediate knight retreat has some drawbacks since white can just play d4 immediately and kick the knight around a bit; note that after 4...Nc5 5.d4! Nd7 white can suddenly play the pawn sacrifice 6.e6! with a nice position.

Looking in my opening database I see that the most common move for black after 4...Nc5 5.d4! is 5...Ne6. In this position it seems like white has a pleasant choice of several good alternatives. For instance, 6.Be3 develops a piece and makes it a bit more difficult for black to play ...c5, while 6.f4!? seeks to gain even more space and to further kick the black knight around.

Basically, after 4...Nc5?! 5.d4! it seems like white gets a phenomenal position with a space advantage typical of the french defense, but without any drawbacks since black's knight loses so much time on its journey around the board.


What were Fischer's 179 demands for a World Championship rematch? According to this video (at 4:25), Bobby Fischer made 179 demands for a rematch for a World Championship, after he won the title. What were those 179 demands?

If it was only about the 1975 match, It could have been a mistake by the video editor. As far as many sources from the web, there were only 3.

Not counting the draws, first to win 10 games wins the Championship.
If the result is 9-9, then the title goes to Fischer but the prize money is split equally.
There will be an unlimited number of games.

The first one was accepted and the other two were rejected by FIDE delegates. Hence the match was forfeited and the champion title was given to Anatoly Karpov, his challenger.

As far as Fischer being concerned who was very demanding in character and liked to impose his own rules, the number 179 could have been total demands throughout his career.

Some other sources mention that he only asked for two rules. You can read the digital version of the newspaper article here: NYTimes

And there is one another source that mentions as per the video. It is the Independent article. I feel that the video editor got the directions from here. Because 179 demands seem very unlikely. If it were true, it is not a World Championship match but some sort of dictatorship.


Is there any website or software that are like "Guess the move" training program in chesstempo? I find the "Guess the move" training program in chesstempo website very helpful. But this is not free and also the number of games is not much (compared to tactics training program which is in the order of hundreds of thousands; while "Guess the move" program contains around 100 games).
Is there any other website or software that is like "Guess the move" training program?

What about the iOS SmallChess app written by myself?

(source: smallchess.com)

(source: smallchess.com)

(source: smallchess.com)

(source: smallchess.com)


What is the earliest queen move in any strong, modern opening? I have noticed a tendency of weaker players to move their queen out very early (e.g. move 2-5), and conversely, a tendency for strong players to move their queen much later (usually later than move 5, but often not until move 7/8/9 or even later).
What is the earliest the queen is moved in any strong, modern opening? By strong modern opening I mean only those used by grandmasters in competition under classical time controls (i.e. meaningful competition games, and no blitz/bullet games).

The definition is still a bit ambiguous, but here's what I found.
The absolute soonest to move the queen is probably the French Defense: Chigorin Variation which begins with 1.e4 e6 2.Qe2.
The Scandinavian with 1.e4 d5 2.exd5 Qxd5 looks like the most common way to move the queen on move 2. I found a game by GM Aleksandr Rakhmanov in 2019 at standard time controls, which ended in a draw.


Search Algorithms used by top engines? what are the top parallel search algorithms used by top engines ,and which one is the best ?
And is there a reference implementation of them in any programming language ? I know most of  the top engines are open source but they tend to be extremely complex and unsuitable for learning .

Best performing algorithms are YBWC and DTS. Lazy SMP is probably giving best performance/complexity ratio. You can read more about parallel search algorithms here (make sure to check referencies and links.
As for reference realization, I haven't seen any, so I just used simpler engines with parallel search,  and, mostly, algorithms descriptions.


What are ways of practicing blindfold chess? Is there a way to practice blindfold chess on the computer?

For example, are there any programs online which give only a transcript of the moves played, and allow you to type in your next move, rather than showing a board?

Not strictly on a computer in your sense I assume, and, depending on how good you are, potentially not challenging enough: A friend of mine did this with an old second hand chess computer. The kind that comes with a board and pieces. The board is touch sensitive to register your moves and has LEDs to indicate computer moves. He played without the pieces.

The advantage: Many of these take batteries and allow you to play anywhere.


Why doesn't 1.fxe4 Nf6 work for black in this puzzle? I was solving puzzles and I failed this one.
The correct answer was fxe4 fxe4 Bxh5+.
Why can the knight not just move to f6 and be safe there?

fxe4 Nf6 exd5 fxd5 is in my opinion more preferable for black.

 [Title "1...Nf6?"]
 [fen "rnbqk2r/ppp3pp/3b4/3p1p1n/3Pp3/1P2PPP1/P1P1B2P/RNBQK1NR w KQkq - 0 1"]

Because after Nf6, e5 is a double attack on the d6 bishop and the f6 knight.

The puzzle aside, given that black's dropping the piece anyway, may as well go for something practical, like Nxg3, hxg3, Bxg3+... and take 2 pawns for the piece, with some positional compensation as the king will be misplaced, but objectively white should of course be easily winning.

 [Title "Puzzle"]
 [fen "rnbqk2r/ppp3pp/3b4/3p1p1n/3Pp3/1P2PPP1/P1P1B2P/RNBQK1NR w KQkq - 0 1"]

 1.fxe4 Nf6 (1...fxe4 2.Bxh5+) (1...Nxg3 2.hxg3 Bxg3+) 2.e5


What types or kinds of chess players are there? I am often asked the question what type of chess player am I, but I am unsure how to answer this question because I do not exactly know what would define each type of player.  Interestingly, I am only asked in particular if I am an attacker or a positional player, but surely, there must be more types of players than these.  What are the types or different kinds of players? Also, if you could include a definition of each type and include any famous players as examples for types, that would be great as well.

There are two broad-brush categories of players: positional and tactical.  Positional players' styles tend to lead them to play moves that choke out their opponents.  They are patient and bide their time.  There's no better proponent of this type of play than Tigran Petrosian. He's recognized as one of the hardest players to defeat.  A more recent example would be Anatoly Karpov, another player that was just so hard to defeat. Positional players keep taking their opponents' good moves away until nothing is left but bad moves.  Aron Nimzowitch was the father of this type of play, though he did not invent it - he described and defined the style in publications such as My System.

There are more tactical players.  These include pretty much all the darlings of chess - the ones scoring points with fireworks.  They tend towards open positions with lots of complexity, relying upon their tactical skills to force an error onto their opponents.  Examples include Rudolf Spielmann, a player from another age who made Tal look tame.  Mikhail Tal is the more modern archetype - a player able to conjure devastating attacks from seemingly nothing at all.  Then there is Kasparov, Fischer, etc the list is rather endless.

In short, tactical players do it to you.  Positional players make you do it to yourself.

At any semi-professional level of play, both styles of player can uncork combinational fu.  So this isn't to say that a positional player avoids combinations and sacrifices.  You won't normally find one player who plays both styles; it is a philosophy sort of thing.  They believe one way is best and sharpen their skills to this belief.


Can white recover? (midgame) If someone could put a picture of the layout in that'd be great, I've looked (clicked edit) on posts with them and I cannot work out the format, also this is a setup, I didn't write down how I got there.

This is a game I was playing against my "Train board" on a train so not my finest work but I ended up in this situation and in the end "resigned" (turned it off), and what I've tried from here

[FEN "r4rk1/pp3ppp/2n1p3/q2p1b2/1b1PnB2/1QN2NPP/PP2PPB1/2R2RK1 w - - 0 1"]

1. g4 (1. Nxe4 dxe4 2. Ne5 Nxd4 {I've noted this was a good move for black, that I missed} 3. Qc4 (3. Qe3 Qd5 4. Qc3 Bxc3) Qd5 4. Qxb4 {play suspected trap for interest} (4. Qxd5 exd5 5. Rc7) Nxe2+) Bg6 2. Qa4 Nxc3 3. bxc3 {Stopped playing, loose queen} 0-1

Now I think (I wrote) that I opened very well and I seemed fairly happy with the moves before these, the move before this starts though I went from waiting room to train and I'm easily distracted by the scenery. So please no "idiot, who does that!" stuff.

I really think black has the stronger position by far, but the midgame can very easily turn.

Can white recover?

White is just fine. Sure, Black stands slightly better due to his better coordinated minor pieces, but the position is roughly equal.

  If someone could put a picture of the layout in that'd be great, I've
  looked (clicked edit) on posts with them and I cannot work out the
  format, also this is a setup, I didn't write down how I got there.

This thread covers the topic pretty good in my opinion.

  I really think black has the stronger position by far, but the midgame can very easily turn.

I believe that opening went something like this:

[fen ""]

1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Bf5 6.Nf3 Nc6 7.g3 e6 8.Qb3 Bb4 9.Bg2 O-O 10.O-O Qa5 11.Rac1 Ne4 12.Rfd1!?

Here, White's last move fortifies  the d4 pawn, leaving e2 pawn free which might be useful in some lines.

Sure, Black has aggressively posted minor pieces, but White finished development and is now ready to push them back. This means that Black will have to make exchanges which will reduce his pressure, or will have to fall back giving the initiative to White.

Therefore, I believe that the resulting position after Rfd1!? is unclear, with chances for both sides.

Since we look at this from White's perspective, it would be good if Black exchanged on c3 and if White could then get Black's lightsquared bishop for f3 knight. With a fortified d4 pawn he could launch e4 in appropriate moment in order to open his position for his bishops. In such position Nc6 would be badly posted since d4 pawn is fortified with c3 pawn.

Just for an example, I provide a sample line:

[fen ""]

1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Bf5 6.Nf3 Nc6 7.g3 e6 8.Qb3 Bb4 9.Bg2 O-O 10.O-O Qa5 11.Rac1 Ne4 12.Rfd1!? Rac8!? 13.Nh4 Nxc3 14.bxc3 Ba3 15.Ra1 Bg6 16.Nxg6 hxg6 17.e4+/=

Best regards.


How can white force a quick win here? This is from a tactics puzzle I encountered today. The given solution was 1. Qxf6 gxf6 2. Bxf6#,” but to me 1... Ne6 seems to halt white in his tracks, even if it does give up a rook.

My moves as white were clearly not optimal, as it "feels" like there should be a better way for white to bring this game to a checkmate

After 1... Ne6, how should white continue?

[FEN "3rrn1k/pp4pb/2pQ1n1p/q3B3/3P3P/1BP3N1/PP3P2/R3R1K1 w - - 0 1"]

1. Qxf6 gxf6 (1... Ne6 2. Bxe6 Rg8 3. Bxg8 Rxg8 4. Qxh6) 2. Bxf6#

Yes, Ne6 staves off mate, but it does not stave off the loss for long, but more importantly, it does not demonstrate the main point of the tactic, which is why they continue with the "worse" gxf6 in the solution.

Technically speaking, the computer thinks that after 1.Qxf6, that 1...Qc7 is the "best" move, in which case, black should just resign anyway after 2.Qxf8+ Rxf8 3.Bxc7.

There was an error in your analysis that lengthens the game also. 3. Bxg8 allows black to take the queen, and win back some of the material, but does not change the outcome.

P.S. This is a common phenomenon, but sometimes in reverse too. You will see site do this, which I believe is correct since you are trying to teach the main point of a tactic; but I have also seen sites use the computer moves as the main line, and thus, miss the point of the tactic from a human perspective.

  [FEN "3rrn1k/pp4pb/2pQ1n1p/q3B3/3P3P/1BP3N1/PP3P2/R3R1K1 w - - 0 1"]

  1. Qxf6 Ne6 2. Bxe6 Rg8 3. Qf7 {But you are up two pieces, and the attack continues with Nh5 next.} (3. Bxg8 $4 gxf6 4. Bxf6+ Kxg8 5. Bxd8)


FIDE norm chance expectation calculation question What is the expected probability that someone rated 2150 will have a performance rating of 2450 over a 9 round tournament and earn an IM norm?

Given the new requirements, I tried to do a calculation. I couldn't find one on the internet suitable for this task, but this one suggests that for one game between a 2150 and a 2450 player, the following probabilities hold (from the standpoint of the weaker player):

win   4.5%
loss 75.1%
draw 20.4%

To get a score of 4.5 or more, which is needed to score a TPR of at least 2450, the following results work:

5 or more wins              (0.0023%)
4 wins, and 1 or more draws (0.0434%)
3 wins, and 3 or more draws (0.0842%)
2 wins, and 5 or more draws (0.0490%)
1 win,  and 7 or more draws (0.0045%)
            9 draws         (0.0001%)
-------------------------------------
                             0.1835%

(you need some combinatorics to get the percentages)

So he will succeed once every 545 tournaments, on average.

It will depend on the strength of the opposition. To take two extremes: if your opponents all have a rating of 1000, you'll always win but never be able to get a TPR of 2450 (9/9 gives a TPR of +700). Conversely, if you're playing nine Stockfishes/Houdinis, rated 3300, you'll score 0/9 but that would give you a TPR of 2600. So the probability you're looking for can be 0%, 100% and everything in between.


Is preventing an opponent from castling considered an advantage? All else being equal, if you have forced your opponent to move their king, thus preventing castling, would that be considered an advantage?

It'll depend on the rest of the position.

If it's relatively open, chances are you can keep the opponent's king in the center and launch an attack. This might well be a decisive advantage; preventing castling on both sides can be much harder than just one side or none at all. It's worth noting that 'artificial' castling (e.g. Ke8-f7, Rh8-e8 and Kf7-g8) takes three moves instead of one, though the rook might end up on a better file than after a regular kingside castling.

If the center is closed and stable, players often don't even castle at all. A king's move to the second row might be enough to connect the heavy pieces. In such a position, being unable to castle is no disadvantage at all.

As @user1583209 notes, in the endgame, the center is usually the place to be for the king, making castling an unattractive option. In general, the fewer pieces on the board, the less of a disadvantage it is not being able to castle.


What is the longest current tablebase mate with a unique optimal line? Having been inspired by an article on ChessBase.com, what is the longest current tablebase mate with a unique optimal line?

By unique, I mean for each of the winning side's plies, there is only one move that gives a shortest forced mate. and for each of the losing side's plies, there is only one move that gives a longest forced mate.

Guy Haworth gives an answer to this in his Chess Endgame Records.

[fen "8/8/7p/7n/k7/8/2K5/3R4 w - - 0 1"]

1. Rd4+! {dtc/m/z = -26/-49/-17m} Ka3 2. Kd3! Kb3 3. Rd6! Kb4 4. Kd4! Nf4 5. Rb6+! Ka5 6. Rf6! Ne2+ 7. Kc4! Ng3 8. Rg6! Ne4 9. Kd4! Nd2 10. Rg2! Nf3+ 11. Kc5! Ka6 12. Rg6+! Kb7 13. Kd5! h5 14. Rh6! h4 15. Rf6! Ne1 16. Rf1! Nc2 17. Rb1+! Ka6 18. Rb2! Ne1 19. Ke4! h3 20. Rb1! Nc2 21. Kd3! Na3 22. Ra1! h2 23. Rxa3+! {KRKP: dtc/m/z = -3/-15/-3m} {Nalimov and Lomonosov DTM EGTs} *

Haworth states that this is the longest-known decisive AUMS, Absolutely Unique Move Sequence, known to the author.

This move-sequence arose from White and Black adopting the following strategies. White's strategy is: first, preserve the value, i.e. keep the position won for White; second, maximize DTM. (Why "maximize" and not "minimize"? I don't know, but in the above line White has only one value-preserving option at each move anyway, so it doesn't matter.) Black's strategy is to challenge White to find the unique value-preserving move.

Every move in the above line is optimal for the player's strategy. In the cases of Black's 20th and 22nd moves, there is not one unique option which is optimal for Black's strategy, but for all Black's other moves the move given above is Black's only option which implements Black's strategy of giving White only one option which keeps the position won for White.

Note that the identity and length of the longest decisive AUMS depends on what White's and Black's strategies are. Black's strategy of preferring "restrict White to a unique winning move" seems calculated to enable there to be long AUMSes. If, instead, Black adopts the strategy "maximize DTM", then the game proceeds differently. 18...Ne1 is indeed Black's only option which gives White only one winning move, but it loses in 20 moves. By contrast, 18...Ne3 loses in 32 (i.e. keeps Black alive for 12 moves more); 19. Kc6 then wins in 32, and 19. Kc5 in 34.

Some of the jargon explained:

decisive: ending in checkmate, not in stalemate

AUMS: Absolutely Unique Move Sequence

DTC: depth to conversion (i.e. depth to capture, promotion, or the end of the game)

DTM: depth to mate

DTZ: depth to changing which ply is the earliest at which a 50-move-rule draw may be claimed (i.e. depth to capture, pawn-move, or the end of the game)

value: whether the position is (with best play) won for White, won for Black, or drawn

Upper-case DTC/M/Z refer to white; lower-case dtc/m/z refer to Black.

Depth is measured in plies, where a ply is either a white move or a black move.

Haworth cites Conrady, 2003; van der Heijden #70232, (2010). The relevant entries in his bibliography are:

Conrady H. (2003). Computerschach und Spiele, Vol. 2, No. iv-v

van der Heijden, H. (2010). http://www.hhdbiv.nl/. ENDGAME STUDY DATABASE IV

The longest AUMS I can see in Haworth which ends with the mating move is a 13-ply KNkp mate. Using Nalimov I have extended it back for a further two plies but only by dint of captures.

[fen "8/8/8/1p6/b1R5/8/N7/k1K5 w - - 0 1"]

1.Rxa4! bxa4 2.Nb4! a3 3. Nc2+! Ka2 4. Nd4! Ka1 5. Kc2 Ka2 6. Ne2 Ka1 7. Nc1 a2 8. Nb3#! {Nalimov and Lomonosov DTM EGTs} *


Transposition into KID I have looked at many grandmaster games where White starts off with 1.c4, which later mostly transposes into a King's Indian. However, Black could have immediately played 1...e5, which seems slightly better. Why would Black not take this opportunity?

It is a matter of choice
Many grandmasters (e.g. world champion Viswanathan Anand) have consistently played 1.c4 e5 with Black. Others favour the KID or other defenses : Hedgehog (with b6), symmetrical English (1.c4 c5), Pseudo-Nimzo (with Nf6 and e6), Pseudo-Grünfeld (with Nf6 and d5), Réti (with e6 and d5) or Slav-like (with c6 and d5) defenses...
There is no definitive hierarchy between all those schemes. You may well prefer 1...e5 and you won't be the only one (this is actually my favorite retort nowadays) but there is no objective reason to think that this choice should be "slightly better" than other reasonable defenses. What suits us doesn't suit everybody.
The case with the KID
The King's Indian Defense has many pluses and minuses: lack of space, ressources for counterplay, long theoretical lines... But one thing that makes it attractive for many players with Black is that the KID is an holistic opening solution for everything but 1.e4 : if you wanna play the KID, you can go for it whether I start with 1.d4, 1.c4, 1.Nf3, even 1.g3 or 1.b3, and there is little I can do to stop you.
As a consequence players who are confident in their KID repertoire against 1.d4 have little incentive to switch to different schemes to meet 1.c4, and prefer to transpose with 1...Nf6 and 2...g6 rather than work on the theory of the pure English 1.c4 e5.


Does practising Lichess coordinates help with reading chess books chess games faster? Some strong players are able to read entire chess games from a book, as they are very familiar with the notation of the chessboard and theory.
For amateur online players, this can be a difficult task and one of the factors that can stop improvement in understanding deeper positional ideas which are explained in this chess notation heavy chess books.
Does practicing coordinates help improve reading? The top scores of titled players are 85 squares in 30 seconds, whereas I average 45 squares in 30 seconds.

I did the test and got 50 squares in 30 seconds. Part of the reason was that it takes some time to move the mouse, but it seems you're quite close to me in speed. I'm also a titled player that can read games from books, so I don't think this is where your problem is.
I'd suggest practicing blindfold chess. Just try playing it a bunch of times with someone, and over time you should get better at it. This helps with reading games from just the notation, since it's the same type of skill being applied.
You mentioned strong players are familiar with theory. This is true, and it includes knowledge like typical opening moves and pawn structures. If the game you are going through (without a board) reaches a position with a structure you're familiar with, or features sequences of moves you've seen many times before, then it's easier to keep track of. If you asked a strong player to read through a game where the 32 pieces start in completely random squares on the board, they would have a harder time since nothing will be familiar.
So to improve your knowledge of theory, the answer here is to just study books on openings, middlegames, etc. Obviously the main purpose of this would be to improve your chess as a whole, and the increased abilities to read games will come as a byproduct.


Is there a good online opening training software? There are a lot of websites to train your tactics, but I can't find any for opening repertoire. I am looking for something similar to 'Chess Position Trainer' but online, where I can import a pgn file with my repertoire, indicate that I want to train it as Black and track my progress. Does such a software exist?

UPDATE/NOTE: being able to train against my own reperoire, and rather than the best tree/stats move is vital for me.

2018 update:

It seems lichess.org offers a lot of the features you're looking for. On lichess, go to tools then choose Analysis board:

The editor allows you to import FEN, PGN or edit the board yourself.
You have access to two proper opening databases, one extracted from the games played on lichess and one from the masters games (top players). It's not only an opening explorer showing the lines, but it also shows you samples of games where a given line is employed.
You can set up your position and play through the opening branches, while simultaneously verifying the engine assessment on the position. From a given position you can also choose to practice against the computer, for instance for a variation you've come up on your own.
Last but not least, once your analysis is done, you can save it all as a study (which can also be made private). As such, all the variations and side-lines you've explored/tried and plan to keep will be saved together with the engine analysis of them. These will be your personal repertoires, which you can continuously modify whenever you find improvements.

The features are available to everyone. Once you've created a couple of repertoires and started practicing them on lichess, in your profile there is an analytics page where all sorts of statistics will be calculated based on your performance. For example, your rate of win with a certain line, or your frequency of certain moves and so on. That will help you to assess how you are performing with your different openings.

Older suggestions:
In terms of simple online opening explorers, there's always the Shredder Opening Database, can be useful for quickly checking something.

Then there's the database available on chesstempo which is actually really detailed (statistics on each opening etc) and gives exemplary games of any opening played by real players.

But I believe for what you want to do, lichess is the go-to choice here.


Can we quantify the handicap for playing blindfolded? Roughly how much ELO does it cost a GM or top player to play blindfolded? For instance, if a 2600-rated GM were blindfolded, against what rating of opponent would they be expected to score roughly 50%? Or, what ELO games roughly correspond to the quality we find when looking at blindfolded games between top GMs (say, 2750-rated) like at Melody Amber?
I'm aware that there will be some variation (e.g. Korchnoi was terrible at blindfold), but there should also be consistency - most top GMs have no trouble playing blindfold and the fact that many top players enjoyed success at Melody Amber suggests none of that group are massively less affected by the blindfold than the rest.
Some estimates I've found online already:

A Chess.com thread where a user considers Larry Christiansen's performances and gauges the rating handicap of playing blindfolded to be about 500 points
A SE post concerning blind players. Here the number 600 points is thrown out there.

These strike me as overestimations (and are called out in the threads themselves for being arbitrary). For example, even the lower bound suggested in the blind players thread (450 points) would make the three top blind players all individually on par with Carlsen or better were they not blind.
As for Christiansen, that's the kind of thing I want to know more about. I presume there are no examples of 2800-rated players testing themselves in blindfold against 2200-rated players. (Examples from say Morphy's time would seem to strengthen my point - Morphy was much stronger than his competition, but his non-blindfold results make very obvious that he was NOT 600+ points stronger, or even close to that, while he had no trouble beating most opponents blindfold.) So maybe we can use examples of 2600+ rated GMs playing against opponents around 2000-2300 to make a judgement?

It depends.
Some can play multiple games at once.
Others would struggle to play just one at a much lower level.
There is no way to apply a correction factor that would work for all players.
I played blindfold as an A player and beat an expert easily.


Do I have to follow the openings moves when the response is different? This question concerns the opening. For example, in the Danish gambit:

[FEN ""]
1. e4 e5 2. d4 exd4 3. c3 dxc3 4. Bc4 cxb2 5. Bxb2

white reaches the desired position. But what happens if the opponent deviates from this move order? Would it still be the Danish gambit? Can I still follow the moves in the Danish gambit or do I have to use other moves? Does an opening variation involve any alternative moves?

You never "have" to follow an opening sequence, especially just for the sake of following an opening name. There's nothing special about the "Danish Gambit"; it's just a group of moves someone decided to give a name. Any sequence of moves can be given a name if people really wanted.  If your opponent plays a different move order or unexpected move you should adjust your play accordingly. But of course there's always a chance you might transpose back into that "Danish Gambit" line depending on what moves are played.


How do you study opening theory using Stockfish? Any tips to be up to date with recent opening theory?

Usually, computers are not very accurate in the openings. I'd suggest using a good database of grandmaster games like Chessbase or Chess365. If you're trying to prepare against somebody or against a variation I'd recommend using Chessbase while running an engine. For example:

e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 a6 5. Nc3 Nf6 6. Be3 e5 7. Nb3 Be6 8. f3 h5 9. Nd5 Bxd5 10. exd5 Nbd7 11. Qd2 11... g6 12. O-O-O 12... Nb6 was the position I was preparing against.

The main line goes 13. Qa5 Bh6 14. Bxh6 Rxh6 but in many games White just gets a worse position. This is unsatisfactory, and Stockfish 6 found an improvement.

Kb1!

If you're curious, go check out how white gets a forced advantage.


Will FIDE extend time limits on certain qualifications given the suspension of chess during Covid-19? We already know that there has been very little FIDE rated chess played in April. There are a number of areas where FIDE has time limits. For example:

Unrated players have 26 months to get results which qualify them for a FIDE rating
Players are classed as "inactive" if they don't play any FIDE rated chess for 1 year
Arbiters are classed as "inactive" if they don't arbit any FIDE rated competitions for 2 years.

Will FIDE look at extending these time limits in view of the current Covid-19 suspension?

We have a partial answer from FIDE:

WHEREAS, since the onset of the Covid-19 pandemic, it has been possible for only a reduced number of FIDE rated tournaments to take place. As a result, it is likely that many players who would under normal conditions be playing rated games will find that they are unable to do so and will therefore be marked as inactive.

The FIDE Council has considered this problem and has decided on the advice of the Qualification Commission (QC) that, from the November 2020 list UNTIL FURTHER NOTICE, the period specified in the definition of inactivity will be increased from 12 months to 24 months.


Are today's top correspondence chess players stronger than those from 5 years ago? On the one hand today's chess engines will stomp those from five years ago no problem, not to mention hardware improves; on the other hand, correspondence chess players emphasize that one can't just rely on the engine to play:

DN: Every how often do you have to change your machine?
WM: I've never changed my 'machine'. If we're talking about my computer for chess analysis, I'm using the same computer I've had since 2008. Modern correspondence chess isn't all about CPU power (although that obviously helps), but more about how you prepare each move and how you work with the engine in tandem with your own ideas. You can get lazy and buy a powerful computer, and probably get to a fairly decent rating on ICCF just parroting the engine, but that's not going to take you to the top ...

Are today's top correspondence chess players able to reliably beat those from five years ago?
Related: Are contemporary chess players now stronger than players in the 90's or 80's?

Yes, mainly due to more advanced theory that wasn't known five (or more) years ago.

Also, while top Correspondence players do indeed combine engines with their own ideas, having an Engine that is a few hundred rating points higher is a definite factor. I find it hard to believe the person you quoted uses the same engine he has for 10 years. If he means the same computer though (so running the most recent Stockfish/Komodo/Houdini on an old computer), that sounds more understandable. In this case he's only sacrificing the amount of speed that a PC 10 years older gives up compared to PCs now.