text:
Is it rude to ask my opponent to resign an online game when they have a lost endgame?
I really don't know if I am correct when I ask my opponent to resign when I am at a 1800-1900 ELO level. I have an Asperger disorder. To me ,endgames are more clear to play than middlegames, and the game loses interest when I think a newbie would win it. I sometimes ask my opponent to resign and play a rematch. Sometimes it has an effect, and they resign. At other times, I feel myself uncouth.
[fen "5k2/1p6/p3pP2/P1p1K2p/2P4P/8/5Bp1/8 w - - 0 1"]

Is it unfair to ask for a resignation in these kinds positions in an online chess game?

I feel that someone else to resign is a little rude, though it might not be a big deal. You should absolutely respect their decision if they don't - it is their choice after all.

Your opponent has every right to play on if they wish.  You should never ask your opponent to resign.

You might be interested: https://boardgames.stackexchange.com/questions/48318/is-refusing-to-concede-in-the-face-of-an-unstoppable-nexus-combo-punishable (although this is for another game, the concepts are the same).

Please note that your opponent may not be aware that his position is lost

A different game (MtG), so a bit offtopic here, but once I was asked to resign a game. I refused, used the opportunity to study my opponent's style (and deck), and won 2:1 (besides, I wasn't convinced he won that match, as I didn't see his cards in hand). You can use a similar situation in almost any game if you're going to play a rematch. Although it seems less important in chess.

@Nyos Quite a difference here, as part of MtG strategy is deck build. The longer you play, the better you understand your opponent's deck construction and what you might have to bring in from the sidedeck. Chess is rather different here, and there is no element of randomness (card draw), so there comes a point where it would take a blunder to swing a game around. Consider a MtG match where both sides know their opponent's deck just as well as their own -- we resign all the time when we can clearly see what's coming and know we have no counter to it.

As @David said, in the position shown it's quite plausible for a relative beginner to think that he can stop the white h pawn from queening, and somehow manage to get a draw by stalemate or else queen one of his own pawns. And if the OP makes some blunders, he might be right!

The body of the text seems to be describing a position that the other player might be in a position to beat you, so you ask them to resign?  Because "the game looses interest when I think a newbie would win it".   That isn't just rude.   You are being an ass.  In that position, you resign, and ask for a rematch.

Do I see correctly that this is correspondence chess? I think the  answer to this might depend on the time control a bit. Could you state the time control?

The fact that you struggle to win is not your opponent's problem.

@Studoku the position in the OP is certainly not a "struggle to win" position. Black is completely busted. 39. Kxe6 Kg8 40. Ke7 and the pawn promotes, or 39...Ke8 40. f7+ Kf8 41. Bxc5+ and 42. f8=Q+. I'd suspect even a beginner can win that position against Stockfish.

@Allure that's my point of view. And it is correspondance, so no sense to play it. But I won't ask it if it is unfair

@Universal_learner Hi, this post seems to have received a number of decent answers, if you have found one to be particularly satisfactory please consider accepting, as it's important to give closure to well addressed posts. And please consider doing so as well for your previous posts, many of them are already well answered but not yet marked as accepted.

I forgot it. Done! Many of them not marked? That's false all my questions on chess exchange were marcked unless this one.

And all my questions on Earth Sciences answered are marked too, so I don't know what you are talking about.

@Universal_learner Thanks for accepting. Indeed you had them all accepted, I had seen your answers section instead of questions.

@user929304 Thanks for advicing me I forgot it in this one, and don't worry.

If your opponent seeks to better themselves at chess then please explain how resigning early per your request helps them get better. It sounds like you are playing against people below your level so you should try playing against people which are actually at your level.

No my oponnent has my level, ~1850 ELO.

@quid It is correspondance chess, 2 days to move, but it seems that, as I didn't mentioned it, most of people thougth it was time control. I changed the picture, but it could be seen in the original screenshoot.

Thanks. Frankly, it's really a  bit odd they don't resign, imo. I mean it's even white to move.  You just pick up the e-pawn and what might you even do to not win? Given the pawnstructure on queenside, there'll "never" be a stalemate. Maybe that's what they don't realize.

Rather relevant, I think:  https://forums.online-go.com/t/go-memes/4337/87?u=eugene

Is it rude to ask my opponent to resign an online game when they have
  a lost endgame?

Yes, it is rude, although you are in good company. In one Olympiad Victor Korchnoi is alleged to have asked his opponent - "Do you speak English?" When they said "Yes" he replied "Then please resign". I may be misquoting. He may not have said "please" :-)
Strictly speaking today what Korchnoi did is not allowed in over the board chess because it is disturbing the opponent. In online chess, however, trash talking is more acceptable because the opponent can always mute by switching off chat.

I sometimes discuse on correpondance eg at move 20 oh my last move on 18th move was a mistake and we discuse it. It is not the same as on board with time control. But I think I should not ask for resign more. Just if I feel boring to end the game I will be quiet and I will accept my oponnent liberty of playing it

@Brian Towers Korchnoi was one of the greatest ever but I wouldn't call him "good company" for treating your opponent with sportsmanship.

@BrianTowers: "Victor Korchnoi is alleged" *** it's wrong to simply repeat this kind of pseudo-information, there is no excuse for doing so.

When Korchnoi said "Resign!" his Olympiad opponent should have accepted Korchnoi's resignation and summoned an official. I take it that's not what happened. How would/should the official have ruled? I would have thought that any use of the word "draw" (or equivalent) would constitute a binding offer of a draw, and any use of the word "resign" would constitute a binding resignation.

One online game my completely lost opponent chatted with me about how lost he was while he set up a stalemate trap.  No chat after his trap didn't work, he just resigned.

Brian Towers answered the question, but to help you understand why people don't resign, I recommend you watch this lecture by GM Finegold Blunders, with GM Ben Finegold. The gist of it is:

Never resign, and look for resources no matter how bad your position
  is. And when you are winning, don't let your guard down.

It should be pointed out that Finegold's lecture is aimed at beginners. For example, at 1:54, he asks the audience what move Black should play and explicitly reminds them that the move White just made attacks Black's queen with a knight. It takes the audience 20 seconds to figure out that the correct reply is to take the knight. The advice to never resign definitely doesn't apply to more advanced players.

He makes a great point in the video about how you can be losing the entire time and then the opponent makes the one move that gives the game away. You don't win a game because you played 20 good moves and the opponent played 20 bad ones, but you win because the game was even until your opponent blundered.

Not resigning in a lost case can mean to spoil your (mental) resources and waste everybody's time.  Also, assuming your opponent could make a very dumb mistake at any time shows disrespect.  Yes, it might be correct, sure, in one of a thousand times.  but the 999 other times you might be appearing to be a jerk.

@Alfe GM Finegold's point is that, if you're a beginner playing another beginner, there's no such thing as a lost cause, because your opponent could blunder their queen at any moment, or fall for a silly checkmate. But, for players beyond that stage in their chess development, I fully agree with what you say.

I think for any level of experience and expertise there is a level below which the game can be called a lost cause.  The advice states that one might be tricked into thinking this too early, especially as a beginner.  But also experts may sometimes think they lost a game and be on the verge of giving it up and then suddenly they see a loophole they overlooked before.  So (even when he addressed beginners) this isn't about beginner/expert, it is more a general advice.  And I would still like to add that one can waste time and mental resources on lost causes following that advice.

"The winner of a chess game is whoever makes the second-to-last blunder".

""The winner of a chess game is whoever makes the second-to-last blunder". – the author of this saying was great Savielly Tartakower.

I'd add, especially in a fast game.

It's always rude to ask your opponent to resign. They should resign of their own accord once they're convinced that you're overwhelmingly likely to win the game. In my case, that always meant you'd have to convince me that you knew how to play the endgame in question and that both of us knew how you would win it.
If your opponent hasn't resigned yet, it might mean that they don't know that it's a lost position for them, or that they're not yet convinced you know how to win it. In any case, in the position shown, it shouldn't take more than a few more moves for you to checkmate your opponent, so it's really not something you should be worrying about.

Another possibility is that the other player knows it's a losing endgame, but still wants to play it out as an exercise.

@N4v Or for that matter, they might have a long-shot novel approach they think might work even to just draw the game.  It might fail 100% of the time, but you might not know for sure until you try (or have seen it before), and hopefully both players learned something in the process.

Honestly it's rude to ask your opponent to resign in any position. The one exception may be them deliberately letting their clock run to 0 in a completely lost position, but in this case they're being deliberately malicious and you can't really hope to reason with them.
Even though you're absolutely justified in thinking your opponent should resign, that doesn't mean you should tell them to.

Also in correspondance master? I think answers may have differed if I clarified it was correspondance.

In correspondence you're even more justified in thinking your opponent should resign, but that still doesn't mean it's nice to ask them to. They have the right to play on for whatever reason.

Ok, I won't do it more.

You might know that you are playing a game that is already decided, but your opponent might not.

Your opponent might not realize that the position you now have is a won endgame.
Even if your opponent realizes it, she might not be convinced that you know that you already won and that you know what mistakes you need to avoid in order to win. So they believe that there is still a small chance that you slip up and they can get a draw or even win after all.

Usually it is considered bad etiquette to discuss the game you are playing with your opponent, but if you really want them to be aware that they are wasting your and their time by continuing this match, then you could use this as a teaching opportunity.
Use chat to tell them (politely!) that they can not win. You could also give them a link which explains how to win that endgame to show them you know exactly how to beat them and that they can't do anything about it. Don't write "You lost, resign already!". Write "I think you can no longer win this game because..." and let them come to the conclusion to resign on their own.
But it is possible that your opponent can not be convinced that they lost no matter what you write. In that case the only way to convince them is by playing the game to the end and win.

I can't agree with the advice to discuss the game with the opponent while it's in progress. Telling somebody that they're in a lost position, even using polite words, is still basically telling them that you think they should resign, and that's still grossly inappropriate.

Not the best way to go, but still incrementally better than asking for a resignation. If the OP can't stand just playing the game without saying anything, this might be a viable alternative. And if OP ever gives away the win by explaining the position, then they'll learn to keep quiet and just play :-).

@Jeffrey This is correspondance. In blitz or quick games I agree to talk can disturb, but on correspondance there is no clock.

Why don't you resign instead?
It's a question that looks like it has an obvious answer: because I'm winning!  But that begs the question "who cares?"
Let the game end.  What happens?  Your record goes up by 1 win, and you get some rating points.  In the end, other than the sheer enjoyment of the game, that's the only real consequence.  A few bits in a computer tracking your record.
Now if you were merely bored with the game, and convinced it is utterly over, nothing stops you from just resigning a winning position and going on with your life.  Perhaps you might play another game in the saved time.
Which means, when you really get down to the trade-off, you are pairing the points you might lose by resigning yourself (to solve your interest issues) against any sheer enjoyment of the game the other party may have.
Which leads to the human question: do you have a sense of how much enjoyment they have left in the game?  Clearly they're not already at the point of saying the game was no longer worth playing, or they would have resigned already.  So you are asking them to truncate that enjoyment for your sake.  You are really telling them that they are no longer worth your time and they are not worth the points it'd take to break free of the game of your own accord.  Whether they agree is really a people problem, and you may get some clues from their move choices and/or their chat.
Maybe they've been looking to try out that difficult endgame to see what they might be able to pull off.  They'll never find out if they resign.  But now they know that any fun they might have trying out that end game is paining you.
There's a few alternatives I might suggest.  One is to do what Allure did in the comments:

Black is completely busted. 39. Kxe6 Kg8 40. Ke7 and the pawn promotes, or 39...Ke8 40. f7+ Kf8 41. Bxc5+ and 42. f8=Q+

Rather than telling them to resign, because they are no longer worth your time, help them see what you see.  Practice teaching people how to analyze the endings.  Then they can decide whether that means its time to resign or if they want to play out a line you didn't analyze.
Alternatively, realize that those bytes in some computer's memory banks somewhere are not really all that important.  Make your own game.  If a position seems totally won, look for a challenge instead.  See what non-optimal play you might be able to bring into the game to make the endgame interesting again.  Maybe you need to hang a bishop, or promote a pawn to a funny piece.  If you have a text-to-speech engine that can call out moves, consider playing the ending blindfolded, just for the challenge.  We teach games to be all about winning and losing, but at the heart of it they're games.  Find ways to have fun with them!

I'm not sure if "Make your own game" is good advice, I don't think it is polite to toy with a defeated opponent.

Truely I have resigned in some cases, and refused to play a rematch. I play correspondance, and in some cases my oponnent took me a week mating him in endgames that are lost as K+R vs K that can take 15 or 20 moves to win. I don't care about points on the net, well I want to have my rating at my level to play with people of my level.

I hate when it happens on federated 90+30 games. There I cannot resign, to me to play a middlegame with plus rook and no counterplay is also boring (and it can take one or two hours to win), and I would also win that to Magnus Carlsen.

Winning and increasing your rating often does have consequences. It can determine who wants to play with you next, and in general I like playing against somewhat stronger opponents.

"See what non-optimal play you might be able to bring into the game to make the endgame interesting again" that would be unfair with my oponnent. I know it since I continued playing a loosed game on an International Tourney at age 8, and my oponnent gave me some chances to think I could draw it or win it. He also told me  I should have resigned. The GM that was with me stayed quiet, but told me after the game "What he has done is neither a fair behaviour"

The answer I am about to give is not directly related to Chess (a game I'm far from mastering),  but any skill based PvP game (opposed to stats-based games).
(Yes, I know that in some cases, the loss is inevitable since you cannot win with one King vs two promoted Queens.)
The other player/team might be losing for now, but the game is not over and the tables may turn.
In my opinion, keep playing a game in the losing position is really important to get better (not only because I feel sympathy for underdogs).
As you have no room for mistakes you have to keep a cool head, play on the edge, take the absolute best decisions if you want to keep a chance of reducing the advantage and, finally, overturning the opponent.
In the other hand, in the winning position, you may have more room for mistakes but you need maintain your best level to keep the lead and widen the gap.
Not wanting to play a game until it's conclusion is either :

a proof of lack of respect for your opponent, as you believe he has no chance (i.e. : is not skilled enough) of getting back.
a vulgar display of vanity of your part, since you're assuming you cannot be overtaken in any way and that you won't learn from the rest of the game.
wishing neither of you get better at the game, because not playing said game will not help any of you improving at it.
showing you are not having fun playing the game anymore, which is... kind of sad.

Yes, asking your opponent to resign is rude, no matter the game/sport if you are playing a competitive ELO (or other system) match-made game.

I would never ask an opponent to resign over the board (live chess), although someone else brought up a good point about an opponent letting the clock run to zero on purpose.
Online, I think it's different.
Online chess, especially at a beginner-intermediate level, is a lot less formal. When sites give you the preset option to request that your opponent resign, I think it's fine to do so once. Chess is different from other sports; resignation is acceptable, obviously, and some argue refusal to resign in a lost position is disrespectful. But regardless, sometimes things come up. I might ask an opponent to resign if I had a dominating position but didn't have the time (in real life, not on the game clock) to finish the game. Or if I had to finish doing the laundry. Or I wanted to go to sleep. I wouldn't actually expect that to work every time, and if you do this you should not take any offense if the opponent refuses to resign and plays out the game. I think it's akin to a draw offer, in that your opponent has every right to continue, but your suggestion might be more convenient.
Asking for resignation in online chess is an agreement, just like asking for a draw.

I might ask an opponent to resign if I had a dominating position but didn't have the time This reminds me of an online game I used to play where opponents were clearly going to lose, but they were aware that my team had a tournament game coming up and couldn't stay to the end. So they kept playing, and we wound up resigning instead ...

I want to emphatize the game is correspondance chess. Close to mark this as the correct answer, but I respeted the votes system.

It depends a lot since if you are playing a bullet game then he might expect blunders so he might not be resigning so, in this case, it is a little rude to ask him to resign. On the other hand, if it's a rapid or classical game and your opponent isn't resigning then perhaps it's disrespectful on his part. I would still say that you shouldn't be asking people to resign either way.

Or he does not agree with your assessment.  Or wants to learn how to actually win by watching you do it in that position.


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Is there any game where AlphaZero wins against Stockfish thanks to a knight pair?
I have seen some of the games that were published in the match between AlphaZero and Stockfish.
In many games, as when it beats Stockfish as black playing the Berlin Defense, AlphaZero appears to obtain some extra advantage of preserving the pair of bishops.
Is there, conversely, any game where AlphaZero beats Stockfish using the power of the knight pair?

Gaining an advantage with the two bishops specifically is far more common than doing so with two knights. The only real way two knights can outperform two bishops is in a completely closed position.

At this level it's hard to determine whether it's "thanks to the knight pair" or "in spite of the knight pair"

@InertialIgnorance but there are many situations with two knights versus bishop+knight!

@David Yes indeed!

I found a game in which AlphaZero wins the game mostly due to the major activity of the knights in the middlegame.
Jeremy, from ChessNetwork, made a great anaylsis on the game.
[Title "AlphaZero-Stockfish, London England, 2017"]
[FEN ""]

1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Bb7 5. Bg2 Bb4+ 6. Bd2 Bxd2+ 7. Qxd2 d5 8. O-O O-O 9. cxd5 exd5 10. Nc3 Nbd7  11. b4 c6 12. Qb2 a5 13. b5 c5 14. Rac1 Qe7 15. Na4 Rab8 16. Rfd1 c4 17. Ne5 Qe6 18. f4 Rfd8 19. Qd2 Nf8 20. Nc3 Ng6 21. Rf1 Qd6 22. a4 Rbc8 23. e3 Ne7 24. g4 Ne8 25. f5 f6 26. Nf3 Qd7 27. Qf2 Nd6 28. Nd2 Rf8 29. Qg3 Rcd8 30. Rf4 Nf7 31. Rf2 Rfe8 32. h3 Qd6 33. Nf1 Qa3 34. Rcc2 h5 35. Qc7 Qd6 36. Qxd6 Rxd6 37. Ng3 h4 38. Nh5 Ng5 39. Rf1 Kh7 40. Nf4 Rdd8 41. Kh2 Rd7 42. Bh1 Rd6 43. Ng2 g6 44. Nxh4 gxf5 45. gxf5 Rh8 46. Nf3 Kg7 47. Nxg5 fxg5 48. Rg2 Kf6 49. Rg3 Re8 50. Bf3 Rdd8 51. Be2 Rf8 52. Bg4 Nc8 53. Bf3 Rfe8 54. h4 Rh8 55. h5 Rhe8 56. Bg2 Ne7 57. h6 Rh8 58. Rh3 Rh7 59. Kg1 Ba8 60. Nd1 g4 61. Rh5 g3 62. Nc3 Ng8 63. Ne2 Rxh6 64. Nxg3 Rxh5 65. Nxh5+ Kf7 66. Kf2 Nf6 67. Nxf6 Kxf6 68. Rh1 c3 69. Rc1 Rh8 70. Rxc3 Kxf5 71. Rc7 Kf6 72. Bf3 Rg8 73. Rh7 Rg6 74. Bd1 Rg8 75. Rh6+ Ke7 76. Rxb6 Kd7 77. Rf6 Ke7 78. Rh6 Rg7 79. Rh8 Bb7 80. Rh5 Kd6 81. Rh3 Rf7+ 82. Ke1 Bc8 83. Rh6+ Kc7 84. Rc6+ Kb8 85. Rd6 Bb7 86. b6 Ba6 87. Rxd5 Rf6 88. Rxa5 Rxb6 89. Kd2 Bb7 90. Rb5 Rf6 91. Bb3 Kc7 92. Re5 Ba6 93. Kc3 Rf1 94. Bc2 Rh1 95. a5 Kd6 96. e4 Bf1 97. Rf5 Bg2 98. Rf4 Rc1 99. Kb2 Rh1 100. a6

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In Fischer-Petrosian 1971 game 7, why did Fischer give up his good knight for a bad bishop?
Fischer played 22. Nxd7, which seems strange since the knight looked very good. Why did he play it?
 [Title "Fischer-Petrosian, Buenos Aires (7) 1971, 10/19/1971"]
 [FEN ""]
 [startply "42"]

  1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Nc6 6. Nxc6 bxc6 7. O-O d5 8. c4 Nf6 9. cxd5 cxd5 10. exd5 exd5 11. Nc3 Be7 12. Qa4+ Qd7 13. Re1 Qxa4 14. Nxa4 Be6 15. Be3 O-O 16. Bc5 Rfe8 17. Bxe7 Rxe7 18. b4 Kf8 19. Nc5 Bc8 20. f3 Rea7 21. Re5 Bd7 22. Nxd7+ Rxd7 23. Rc1 Rd6 24. Rc7 Nd7 25. Re2 g6 26. Kf2 h5 27. f4 h4 28. Kf3 f5 29. Ke3 d4+ 30. Kd2 Nb6 31. Ree7 Nd5 32. Rf7+ Ke8 33. Rb7 Nxf4 34. Bc4 1-0

Correct me if I'm wrong, but wasn't this the exact move that many GM commentators were discussing live as a huge mistake? Ultimately, Fischer proved it right, but if it stumped the GMs watching, then this is almost certainly a difficult question to answer.

I have never heard the story surrounding the commentary of the actual game, so I do not know that.

Yasser Seirawan analyzes this position in one of his books. The conclusion is, White trades a super knight for a super rook (after 23. Rc1).

Amateurs master the rules.Champions master the exceptions

It's not really a very bad bishop, is it? The d-pawn was sure to move soon anyway, and the a-pawn wasn't much of an obstruction for the bishop in the first place. After 26. ... h5 it was a different story, but black only did that after the bishop was gone.

And it's also not that good of a knight at that moment, right? Sure it looks well anchored (although black's about to undo that with a5), but it also has no moves except Nb3 and Nd7 (played).

GM Daniel King is currently working on his "Road to Reykjavik" series, in which he goes over every game of Fischer's journey through the candidate matches. At the time of writing this, he has just finished his review of game 6 between Fischer vs. Petrosian, so this game is likely to be covered in some detail by him quite soon.

This is a very famous position. Well, here are some reasons, and there are quite a few:

Since this was a Candidate’s Match to qualify to play Spassky, it comes down to exact calculation above all. Fischer calculated that it was good, and his judgement bore out since the game only lasted another 12 moves. Here are some things that probably contributed to this judgement.
It was clear that black had to take with the Ra7 so as not to lose d5, and after that, neither black rook remains well placed since the Ra8 cannot leave the a6-pawn undefended, and either the Rd7 or the Nf6 is stuck defending d5. D5 also limits the scope of the Rd7, in particular.
It also leaves the a6-pawn particularly weak since the Bd7 might have been able to defend it. GM Mikhail Suba is famous for saying "Bad bishops defend good pawns!" In addition, when you look at the minor pieces that are left, the Bd3 versus the Nf6 is clearly in favor of the B and its nice scope. It is of note that if black tries to liquidate the weak a6-pawn with a5, white can just push, creating a dangerous passer.
Lastly, and most importantly in this position, the white Ra1 immediately takes the only useful file, the c-file, with an immediate threat of Rc6, thus black played Rd6 stopping it, which allowed white to take the 7th rank.
In all fairness, the computer finds both 22.a4 and 22.Rc1 stronger by about half a pawn, but Fischer’s method is clear, and very straightforward.

This highlights the fact that there's more being exchanged than just pieces; Fischer was focused on trading advantages. He gave up a strong knight outpost and in return he got full control of the only two open files on the board and also bishop v knight in an open position. It's a good example of Steinitz's "accumulation of small advantages."

22. Nxd7+! Fischer trades one advantage for an even bigger one: the invasion  of the White Rooks.

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How much is the king worth material-wise?
In chess classes, I have been told either that king is worth an infinite amount of points or 10 points. What is the actual material-worth of the king piece?

Welcome to [chess.se]! The answer in the linked question also discusses the 'tactical' strength of the king and gives it a point value.

The question is meaningless. What do you mean with "worth"?

Both sides always have 1 king, so there's usually no situations where the value of the king matters.

The value of the King is infinite, but its power is about that of a minor piece.


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Why is the Exchange French considered drawish?
Why is the Exchange French considered so drawish since it is very early in the game, so it seems like there would be a lot more play left. A lot of lower rated players play it against me, although I am not that strong myself.

Well, first, when you are lower-rated, there really is no opening that can be considered drawish since it takes a fair amount of skill to be able to draw at will. That is often a skill associated more with the Grandmaster ranks, and maybe some solid IMs too.
Assuming that someone has the skill to draw, it really comes down to the ability to exchange pieces to get to an even endgame, mostly the rooks on the e-file, but also the Bc1 might go to f4, when black will want to trade off the well-placed piece rather than keep the B on e7, where it inhibits the rook trades I just mentioned. This trade is advantageous to white since although his B is not super bad, it is still technically a bad B for good B exchange that might be most troublesome for black if they get to certain endgames later.
Another thing that is interesting is that the Exchange French has a quite a number of players, who have overwhelming scores with it. None other than Kasparov played it three times in tournament games against Bareev, Short, and Kortchnoi. He scored 2.5/3. Other undefeated GMs include: GM Najat Abassov was 4/5, Michael Adams 4.5/5,  GM Dmitry Andreikin 6.5/9 (and there are plenty more, but it would have been a project to keep going). GM Etienne Bacrot had one loss, but has a record of 13 wins, 1 loss, and 3 draws with it as white. I think that this is because there can be significant danger if your opponent assumes that you are trying to draw, when you are really trying to win.
I played 1.e4 until I was 1935 USCF, and I played a line of the Exchange French with an early Qf3 that I found Kortchnoi had played with success. My OTB record with that was 6 wins, 1 loss (In the very first game with this as a 1700, in a winning position, I let my queen get trapped…oops).
Granted, my opponents were weaker then, but what I found was that black never paid enough attention to the e-file, which was their downfall. The other point is comfort: Many French players do not like this type of position, while white must be reasonably happy since he is playing it. Having “your kind of position” is a major part of winning chess. I would double the pawns on f6, and take the file, and just win; or trade a N for a B on e6, and what was left was bad. Here are examples of each.
[title "Kevin Cotreau 1735 - Terry Messa 1830, Cole Younger Open, 1984"]
[fen ""]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Nc6 5. c3 Bd6 6. Qf3 Qe7+ 7. Ne2 Nf6 8. Bg5 Be6 9. O-O h6 10. Bxf6 gxf6 11. Ng3 O-O-O 12. Nf5 Bxf5 13. Bxf5+ Kb8 14. Nd2 Qf8 15. Rae1 Qg7 16. Re3 Ne7 17. Bh3 Ng6 18. g3 c6 19. Rfe1 h5 20. Bg2 h4 21. Nf1 hxg3 22. fxg3 Nf8 23. Re8 Ne6 24. Rxd8+ Rxd8 25. Ne3 Ng5 26. Qg4 Re8 27. Kf2 Ne6 28. Qf3 Qg6 29. Nxd5 Rh8 30. Nxf6 Rxh2 31. Nd7+ Kc8 32. Ne5 Bxe5 33. Rxe5 Qc2+ 34. Re2 Qg6 35. Kg1 Rh6 36. Re1 Qf6 37. Qxf6 Rxf6 38. Bh3 Kd7 39. Rf1 Rxf1+ 40. Kxf1 Ke7 41. Bxe6 Kxe6 42. Kf2 Kf5 43. Kf3 a5 44. g4+ Kg5 45. c4 f5 46. gxf5 Kxf5 47. Ke3 b6 48. a4 Kf6 49. Ke4 Ke6 50. d5+ Kd6 51. Kd4 cxd5 52. cxd5 Ke7 53. Ke5 Kd7 54. d6 Ke8 55. Ke6 Kd8 56. d7 1-0

and
[title "Kevin Cotreau 1735 - Gary Field 1940, NH Amateur, 1984"]
[fen ""]

1.e4 e6 2.d4 d5 3.exd5 exd5 4.Bd3 Bd6 5.c3 c6 6.Qf3 Be6 7.Ne2 Qc7 8.Bf4 Ne7 9.O-O Nd7 10.Nd2 Ng6 11.Bxd6 Qxd6 12.Bxg6 hxg6 13.Qg3 Qe7 14.Rfe1 O-O-O 15.Nf4 Qf6 16.Re3 Rde8 17.Rae1 Nf8 18.Nf3 {idea Ng5} 18...Nh7 19.Nxe6 fxe6 20.Qd6 Nf8 21.Ne5 Qf4 22.h3 Rd8 23.Qe7 (23.Qc5! Kb8 24.Rf3 Qd2 25.Rf1+– {The ideas of Rf7 followed by Nc6, or Nf7 are unstoppable.} 25...Nd7 (25...Qxb2 26.Nf7 Nd7 27.Qd6+ Kc8 28.Nxh8 Rxh8 29.Qxe6+–) 26.Qd6+ Kc8 27.Rf7) 23...Qh4 24.Qxh4 (24.Qa3! Kb8 25.Nf7+–) 24...Rxh4 25.Rf3 Re8 26.Rxf8 Rxf8 27.Nxg6 Rff4 28.Nxh4 (28.g3?? Re4) 28...Rxh4 29.Rxe6 Kd7 30.Rg6 c5 31.Rxg7+ Kc6 32.dxc5 a5 33.Rg4 Rh5 34.b4 a4 35.Rd4 Re5 36.Kf1 Re6 37.f4 Re3 38.f5 Rxc3 39.f6 Rc1+ 40.Ke2 Kd7 41.Rxd5+ Ke6 42.Rd2 Kxf6 43.Kd3 Kg5 44.Rc2 Ra1 45.Kc4 Rb1 46.Rc3 {To prevent a2 and Rb2.} 46...Rb2 47.Ra3 Rxg2 48.Rxa4 Kh4 49.b5 Kxh3 50.Ra3+ Kh4 51.c6 Rg4+ 52.Kc5 Rg5+ 53.Kb6 bxc6 54.bxc6 Rg6 55.Kb7 1–0

Ultimately, if you find this to be a real problem, then you might want to just play something else when facing players, who are much lower-rated since most higher-rated players probably will not play it to begin with.

At lower levels, it's certainly not drawish as there is a chance to use the outpost in the open file (as well as some manoeuvering towards the f5 (f4 for Black) square, which is great for knights), and games with opposite-side castles are possible. A c4 (or ...c5) break is also possible turning the position into an isolated central pawn one, which isn't more drawish than any other position
At top-level play, it tends to be drawish because of the symmetrical pawn structure and the open file (where a lot of trades will happen). Many minor piece endgames with a small advantage for either side will often result in a draw.

The exchange variation of the French defense has symmetrical pawn structures with an open file. Symmetrical pawn structures make it difficult to create imbalances which lead decisive games. Then the rooks and/or queen will get exchanged along the open file. Fewer pieces coupled with a balanced position is drawish.


text:
In Damanovic-Fischer, 1970, wasn't 66. Ke3 better?
In Damanovic-Fischer, it seems like the move played, 66.  bxa4+, made it easy for Fischer. Wasn't 66. Ke3 better?
       [Title "Damanovic- Fischer, 1970,"]
       [FEN ""]
       [startply "130"]

       1. d4 Nf6 2. c4 c5 3. Nf3 cxd4 4. Nxd4 Nc6 5. Nc3 g6 6. e4 d6 7. Be2 Nxd4 8. Qxd4 Bg7 9. Be3 O-O 10. Qd2 Be6 11. f3 Rc8 12. Nd5 Nd7 13. O-O Nc5 14. Rac1 a5 15. b3 Bxd5 16. cxd5 Qb6 17. Rc4 Qa7 18. Rc2 Bh6 19. f4 Rc7 20. g3 b6 21. Rfc1 Bg7 22. Bb5 Qa8 23. Qe2 e5 24. dxe6 fxe6 25. Rd1 Rd8 26. Bd4 Bxd4+ 27. Rxd4 e5 28. fxe5 dxe5 29. Rxd8+ Qxd8 30. Bc4+ Kg7 31. Bd5 Nd7 32. Qf2 Rxc2 33. Qxc2 b5 34. Kg2 b4 35. Qc6 Nf6 36. Kf3 Qd7 37. Qxd7+ Nxd7 38. Ke3 Kf6 39. Kd3 Nb6 40. Bc6 Ke7 41. h4 h6 42. Ke3 Nc8 43. Kd3 Nd6 44. Ke3 Kd8 45. Kd3 Kc7 46. Ba4 Kb6 47. Ke3 Kc5 48. Bd7 Kb6 49. Ba4 Kc7 50. Kd3 Kd8 51. Bc6 Ke7 52. Ke3 Ke6 53. Kf3 Kf6 54. g4 g5 55. h5 Ke7 56. Ke3 Kd8 57. Kd3 Kc7 58. Ba4 Kb6 59. Bd7 Kc5 60. Ba4 Nc8 61. Be8 Ne7 62. Ke3 Ng8 63. Bd7 Nf6 64. Bf5 Kb5 65. Kd3 a4 66. bxa4+ 66... Kxa4 67. Kc4 Ka3 68. Kc5 Kxa2 69. Kxb4 Kb2 70. Kc5 Kc3 71. Kd6 Kd4 72. Ke6 Nxe4 73. Kf7 Nf2 74. Kg6 e4 75. Kxh6 e3 76. Kg7 e2 77. h6 e1=Q 78. h7 Qe7+ 79. Kg8 Ne4 0-1

I love the last move of the game, 79...Ne4. After the forced 80.Be4 Ke4 81.a1(Q) Qd1+, he trades on a1, and then plays Kf4 winning the simple K+P ending that is left.

This was played almost at Fischer’s height of strength, so he almost surely would have won anyway after 66.Ke3 also. I think that white thought two things by playing 66.ba. First, that it reduced the number of pawns, which is almost always good when you are in a worse, or losing, endgame. Second, that the bishop might be able to defend a2 along the a2-g8 diagonal.
After 66.Ke3, white will fall into zugzwang due to his bad bishop, or at least, he believed he would. If that happens, the black knight can do some pretty fancy high stepping. This is what I found, but it turns out there actually is a miracle draw, but it is doubtful that any human would have put his B on a4 (to stop Nc4; bc b3 queening).
So, I guess, considering that miracle possibility, the answer is a firm "yes, it would have been better".
[FEN "8/8/5n1p/1k2pBpP/pp2P1P1/1P1K4/P7/8 w - - 0 66"]

1. Ke3 a3 2. Kd3 Kc5 3. Ke3 Ne8 4. Kd3 (4. Bd7 Nd6 5. Ba4) 4... Nd6 5. Bd7 Nc4 6. Be8 Nb2+-+

At the end of the line, the N either gets Nd1-c3-a2 or the Kc5 gets to d4. In either case, winning easily.

Thank you again, Brian. One of these days, I am going to figure out why that will not work for me.

The position after bxa4 seems a lot harder to assess as now you also have to deal with the black king entering. Without bxa4 it seems quite easy to see that you can prevent the black knight from entering via c3, d4 or f4 by just covering the squares b5, c6 and e6 at the right moment with the bishop. So Damanovic must have seen the Nc4 idea and did not find a defense.

@user1583209 Maybe, but you have to see that in its entirety right at that moment. If you do not see Ba4, again not a typical human idea, then at that level, he might have seen zugswang coming as you said. I have it much easier using a computer to check my work. :)

Instead of heading for a4, can't the wB simply defend on the c4-g8 diagonal, e.g. 3...Ne8 4.Kd3 Nd6 5.Be6, intending to pass with Bg8-e6-g8 or Kd3-e3-d3 ?

You are correct, 66.bxa4+ is an inaccuracy and gives Black a winning advantage. Stockfish gives 66.Ke3 a -0.64 evaluation, which remains constant as it quickly reaches higher depths of searching (+depth 60). This indicates the game was probably objectively a draw if White hadn't captured on a4 (though it wouldn't have been fun).


text:
Is it possible to reach master level without studying theory?
Wikipedia page for GM Granda from Peru says:

Julio Granda does not study opening theory. He has said that he has
only read a chess book, the third volume of the General Chess Treaty
of Roberto Grau. Anyway, he admits reading magazines and reviewing the
Informant, which together with his excellent memory and assimilation
capacity, has allowed him to win important tournaments and titles.
Google translation from spanish wikipedia.

Is this possible? Can one become a master without studying theory at all?

There is a serious difference between "theory" and "opening theory". I am pretty sure Granda studied endgame theory, middlegames pattern, etc., if only from the Informant volumes he was reading.

Anything is possible.  The real question is how likely are you and most people to do it that way.
And it depends on what you call 'theory'.
I read NO theory. But I read a lot of practical books on openings, tactics, end games, pawn structure, positional play, yada yada.
They claim that an AI program learned to play Go by playing itself.  I do not know anyone humans that have done that.  We might if we lived millions of years but in reality humans can't do it that way.  Most humans learn by seeing how others,  who win doing it, have done it;  and try to improve on that if possible using the basic tools they learned from practical books.

Absolutely, although I do not agree that Julio Granda is a good comparison since it sounds like he has a near-eidetic memory (close to photographic). It sounds like he also absorbs enough that he has, indeed, learned a lot of theory even if not through sitting down and opening books or a computer. I do believe that to get to the IM and GM ranks, you do need to study theory, or you will lose too many games in the opening.
As for becoming a "normal" Master, I am one, who never studied theory. That said, you still need to learn how to play opening pawn structures, and their basic plans. I got to 2298 USCF, and I know incredibly little about theory, but I do understand what I am aiming for in my openings, and what to do should both my opponent and I end up on our own theory-wise.
Lastly, the difference is that there is a huge difference between IM/GM and we mortal "PhishMasters" (fish, aka phish, among masters).

I think he is autist. I am interested in that case because I am asperger. I have not a developed eidetic-memory, but I have that short time memory. I am wondering if I should not study many books as Granda. My purpose is more humble. To reach from 1800 to 2000 to play on good tables on regional tourneys. Thanks for the answer.

First, you are welcome. I have a friend, who is not autistic, however, has a near-eidetic memory and is an IM. I do believe that if you are capable of absorbing a lot of opening knowledge, then you should. It will definitely be very helpful. Of course, there is more to learn, and how well you practice visualizing the board when analyzing will also help you go far.


text:
Pros and cons of playing correspondence chess
I play correspondence daily.
My reason to do it is I am weak in openings and I can survive to the middlegame because I have access to databases; and I want to learn how to survive the opening and to play properly at 90+30 over-the-board games.
Do you think playing correspondence is a good way to improve?
What are the pros and cons of spending time playing correspondence?

Are you talking about correspondence chess with engine assistance or without?

@Akavall Without asistance. At my level, 1900 on lichess, I play without engine. I must be playing against players that do not use engines as my federated rating rounds 1800

But from answers it looks at a higher level computer asistance is frequent

@Universal_learner It depends on the site; some allow it and some do not.

According to friends who play correspondence chess they report the following benefits:

Variety - you play lots of games all at the same time. Although you might not match Claude Bloodgood, who allegedly had hundreds of games in play at the same time when his postage costs were paid for by the US taxpayer because he was on death row, you will play all your games in a round robin at the same time. So, if you are playing in a 10 player double round robin you play all 18 games at the same time.
You have time and motivation to learn, particularly openings. With typically several days per move you can do serious research into the openings you choose to play, learning the ideas and plans for both sides. Unlike over-the-board you do this during the game when it can affect the result not after when you have already lost.
You eliminate blunders. All your moves are checked by the engine.
You learn how to use engines properly. Again this happens during the game not like OTB after. I often run my finished games through the engine to spot blunders and missed tactics. You will be looking for interesting ideas in games still in progress. You will be checking out the engines 3rd or 4th suggested move because it looks really interesting.

All of these things will help improve your OTB chess by making you think more deeply and intelligently about your moves.
Funnily enough my correspondence playing friends don't think their are any cons! I'm not so sure. From the pleasure perspective they miss out on the adrenaline rush of blitz and even just the excitement of bad moves by either side. If I play a really good move I like to see my opponent sweat. That just doesn't happen in correspondence chess.

Make sure to know the rules before you use engines; some places allow it and some do not.

Points 3 and 4 may be true for highly rated players, but at my level, 1900 at lichess, as a non engine user, I don't find troubles to have a rating equal or higger than my fed rating on 90/30 games. Have I played against computer users? For sure but not in the most of my games. I cannot beat an engine playing 3rd and 4th non loosing lines

One "con" is that since you can spend hours on a move, you may end up spending hours on a move, and then wonder where your day went. :-)

If you are a slow mover when playing OTB, maybe playing Corr makes this worse.

Frankly, the biggest con is that today's correspondence game has turned into computer vs. computer contests. So yes, you learn how to use the computer well, but you may as well play your own computer daily since there is very little difference.

I play maybe in the safetiest place, lichess. At other sites or higher ratings you migth be totally rigth, but I can be sure most of my oponnents don't use engines because my fed rating rounds 1800 on Spain and without wraping my neurones as over the board, I am in 1900 at the site on correspondance. I was asking more about things as the analysis board may harm your capability to calculate lines from a static position. But thanks for clarifying if I reach my level I will met for computers for sure. I don't want that.

I get angry when analyzing with stockfish I find obvious players that use a computer to have my rating then stops using it and loose rating, then they use the engine again to play at 1900 level. I use to flag

Well, I think the biggest thing is that if you enjoy it, continue to do it. :) I still think that there is too much room for computer use for my liking.

The other option on servers is to play blitz good master. Magnus Carlsen only plays bullet at lichess. Well he is more exposed to cheating. I play 10+0 sometimes. There I can be playing with an engine too. And on correspondance I analyze a bit games with a physical board. I think I learn. For the moment cheaters are a minority.

My understanding of modern correspondence chess is that it's mostly a computer vs. computer slugfest. Everyone will be using computer assistance - in arenas where computers are "banned", there are many, many cheaters - and the winner is the one who feeds their computer better ideas (although they are very strong, computers still have blind spots where human input improves their play). Playing without computers is suicide. Even with it it's very time intensive if you want to win at the highest level, because chess is probably drawn with best play and humans operating a strong computer are so close to perfect that it's very hard to win.
Because so much of your time is spent working with your computer, and you won't have a computer in OTB play, you probably won't improve a lot by playing correspondence chess. However, you will learn a lot about openings, because opening preparation is where the biggest edge in correspondence chess comes from.
Quoting top US Correspondence Chess player Wolf Morrow:

DN: Many players of the past were correspondence chess players. I think also today it's quite important, for improving to practice correspondence chess. What's your opinion about this?
WM: It depends on what you want to get out of modern correspondence chess. For me, I found it's a great tool to learn new openings or get a better understanding of main lines. As a result of my CC games, I'm more familiar with the Sicilian Sveshnikov than I would have ever learned as a passing interest in say a chess book or video on the subject. I've also heard and actually seen for myself that top OTB GMs will often use winning approaches taken directly from correspondence games, and then they get all the credit for coming up with this 'brilliant' new novelty to win the game. As I said, I've seen this happen on more than one occasion, and I say to myself "Uhh, no. He didn't invent that move, it was played 3 years ago on ICCF and we CC players are quite familiar with it".

There is traditional correspondence and now a version played over the internet.  You appear to be talking about the internet version. For me there is no real advantage. You might find it less stressful to take more time for a move.  Con is that you will really not improve by doing that.
If you want to play OTB better then you will need to learn openings.  Pick ONE  and master it for white.  Have a defense for black.  Learn both of them and do not try to learn others.  There are just too many.  Learning principles is better than memorizing moves but you should be familiar with your openings so you do not waste clock time at OTB.
You should also learn basic tactics so you can recognize them OTB and not have to hope you can discover them on your own during a game.
Next you should learn end games. Finally learn middle game and positional strategy.
You learn by studying not by playing any speed chess.  You improve by playing people just slightly higher rated while also spending time learning so your rating improves faster.


text:
Finding New York City tournaments as a visitor from Moscow
I am visiting New York City from Moscow. How can I find tournaments there?

If you are visiting New York City and like chess, the Marshall Chess Club is a natural place to visit, whether or not they are currently having a tournament: https://www.marshallchessclub.org/

It may be assumed but would be clearer to state specifically whether you want to enter or merely observe the tournaments.

Most tournaments in the U.S. are not FIDE-rated, but there are some. Your best best are the more-common USCF-rated tournaments. You would have to join the USCF as part of that.
They have a list of tournaments here. Just pick the state you want, in this case, New York.


text:
Is it inadvisable to analyze or play long chess games on a smartphone?
I play a lot of online chess, but I am a federated player whose objective is to play well over-the-board games with 3D pieces.
During my hourly tactics exercises I turn on the computer and do it in the big screen because my results are better than on the smartphone.
For timed games I also play with the PC, as I am quicker with the mouse than with the finger.
But I also play correspondence daily; I use to have 20 games in progress.
I am getting used to analyze and make the moves on my smartphone, when I am not at home, or when I feel too much lazy to turn on the computer.
I know the best is to analyze on a physical chess board, which I sometimes do on correspondence when the position is interesting.
But my question is if I should be less lazy and turn on the computer when analyzing deeply with the analysis board.
I know, in deep, this is a neurology question, but at neurosciences SE they would say it is a question for a chess teacher or highly rated player as there are not specific neurology studies on it.
Just asking, as a 7 years old student could ask: "Teacher, should I always play on the PC or I can use my smartphone playing on the free net?"

It sounds a lot like you answered your own question unless a PhD in neurology shows up to give you some better answer, I think this is going to be people mostly giving their opinions. My opinion agrees with yours: Physical board is best>decent size screen is next best>small screen is worst.

@PhishMaster I am waiting for those opinions and thanks for yours. I know it is a tricky question.

That is why I did not submit a formal answer. :) I also do not answer programming questions, and no longer answer rules questions. I stick to the pure chess stuff, and how to get better.

If you want to see which can analyze faster, try using the same engine and max thread count on both. One test described as such:  "My favorite test is how long it takes the engine to realize that Nxf7 is not the best move for white in the traxler counter attack: 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 Bc5 now 5.d4 and 5.Bxf7 are the best moves but at low depth, especially with mobile engines from 2016-2017, the engines think 5.Nxf7 is good. Even now at depth 30 in lichess, it doesn't see it. You have to wait for depth 32." This is just an example of some kind of "standardized" test to do.

Advisable to use smartphone?  Not really. Okay occasionally if you must look at a position.
As you noted a PC is more helpful to seeing the board and planning your moves.
I have found no difference between using PC screen adjusted to my preferences and using a real chessboard with physical items on it.
For me the difference between chess sets and boards is more than the difference between my preferred set and board and the PC screen with my choice of size and font.
Note that moving the men on your phone or pc will negate any OTB experience for a tournament that you would get by analyzing without moving them to improve your analysis vision for 'real' chess in an OTB tournament.

I know the scope of the question is not health related but there are concerns for the levels of electromagnetic radiation that we are exposed to from our phones. It is a minor carcinogen in some high doses at least in lab rats. But to answer the real question I think anywhere you play is a bonus and will help but recreating as close as possible the actual environment for which you hope to compete is ideal but if the option   is less practice then use the phone but adjust the times to allow for your slower plays but you need actual times to get used to the appropriate timing so everyday make sure you get some big screen time at actual or faster speeds than you will face
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5504984/

There is no proven radiation problem with smart phones.  Look at radio amateurs and others who sit next to high power transmitters for long periods with no problems.  Look at all the people immersed in wifi radiation all the time.  If there were a real problem we would know.  There are always some people finding fault with anything we do or eat or think and say it causes a problem.

There is a growing body of evidence that there may be reason to be cautious I will link the study that the world health organization did that concluded that there is a cancer and health concern. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5504984/


text:
What is the Bongcloud opening?
I have heard the Bongcloud opening mentioned on chess.com, but I have never heard of that. Is this a real opening, and if so, what is it?

The Bongcloud opening is a joke opening that is meant to give your opponent a chance, and also it is meant to show contempt for your opponent. You play it because you think you are much stronger than they are. It is, obviously, not a good opening.
GM Hikaru Nakamura is one of the jokesters, who plays this from time to time. There are multiple YouTube videos showing him playing this. Here is one.
 [FEN ""]

 1. e4 e5 2. Ke2? {The Bongcloud!}

P.P.S. I was just thinking, and there is another such opening that we used to call "The Fred". It is just 1.f3, and 2.Kf2 (or f6 and Kf7 for black).

Of course, advanced players will know the correct tactical response to this opening: 2... Ke7!!

It's apparently also a chess tradition to annotate Bongcloud games "seriously", even though it's of course a joke.

-1: It's completely unacceptable to explain Bongcloud without bringing up the definitive guide, "Winning with the Bongcloud" by BM Andrew Fabbro published in 2010. (It also mentions the alleged origin of its name, Lenny_Bongcloud.) Also the Botez gambit is irrelevant to the answer, which should be removed.

@Voile just wondering how you managed to downvote this, since your rep is below the limit. Does this site have different rules?

@polfosol When you don't have the 125 rep, the downvote is registered, but it does not really do anything. It is more to make him feel good.

First Voile, my answer is fine. You are free to provide an additional answer if you want to.  Second, I did not argue anything. I stated a fact, and then added an opinion. Your whole attitude about my answer is disrespectful.

The Bongcloud is an opening meant to

Give your opponent a chance

Show contempt for your opponent(if your opponent is terrible at chance)

Create a lasting psychological effect, thus generating winning chances against much better players.

No, the Bongcloud is not a real opening, but it has a close cousin called the 'King David's opening'.

e4 c5 2. Ke2[book move!?]

I don't think number 3 is correct. If anything you create losing chances against much weaker opponents

The Bongcloud is named that based of a chess.com user named Lenny_Bongcloud ( https://www.chess.com/nl/member/lenny_bongcloud ) who used it religiously in thousands and thousands of games.
Andrew Fabbro then wrote a hilarious opening book parody named Winning With The Bongcloud (PDF: https://i.4pcdn.org/tg/1401479151063.pdf ) that catapulted Lenny_Bongcloud's obscure opening into popularity at places like Reddit's Anarchy Chess subreddit.
The rest is history.


text:
Portisch-Radulov, Moscow 1977. Doesn't 16.c5 lose a pawn?
[title "Portisch-Radulov, Moscow 1977"]
[fen "2r2rk1/pb1n1ppp/1ppqp3/8/2PPQ3/1P3NP1/P4PBP/R2R2K1 w KQkq - 0 1"]

Doesn't 16.c5 just lose a pawn?

The short answer is “no” due to the tactics after 16. c5 bxc5 17. dxc5 Nxc5? 18. Qb4 Qe7 19. Rdc1 winning the piece. This is a famous combination from some books I have read.
The position is really a lot deeper than just that tactic, and it is worth mentioning that great move, and why Portisch played it.
First, even though not all of this came to fruition, Portisch probably thought about a lot of this. c5 did the following things:
It deadened the Bb7 on the more important h1-a8 diagonal. It might still have found a home on the f1-a6 diagonal, but there it would not be anywhere near as effective on that diagonal since there was nothing to attack there. It made it a partially bad bishop. Later, on move 25, Portisch also made the great decision to trade on d5, leaving a good N vs. bad B. That affected the game to the end when he finished with a pretty combination.
Although black will get control of d5 with Nf6-d5, with tempo even due to the Qe4, the d6 square looks like a very nice spot for the Nf3-d2-c4-d6. It might take four moves to get there, but it would have been very powerful on that square. It turns out that how the game played out, Portisch preferred to put the Nf3 on e5, where it still was intolerable, and kept black tied to c6. Note that, as Fischer said, you have to give squares to get squares; but I will add that if they are for knight outposts, usually it is a good trade if your knight outpost is much deeper in the opponent’s territory that his is in yours. So, giving up d5, which is not even on your side of the board, in exchange for an outpost on e5 or d6, it is a good trade in most cases. It can really divide the board for your opponent when it is posted that deeply on the other side of the board. As it turned out, black felt forced to weaken his king-side and dark squares further with f6 because the Ne5 was so well-placed.
 [Event "EU Team-ch06 Final"]
 [Site "Moscow"]
 [Date "1977.04.??"]
 [Round "6.1"]
 [White "Portisch, Lajos"]
 [Black "Radulov, Ivan"]
 [Result "1-0"]
 [ECO "E08"]
 [WhiteElo "2625"]
 [BlackElo "2500"]
 [PlyCount "79"]
 [EventDate "1977.04.13"]
 [EventType "team-tourn"]
 [EventRounds "7"]
 [EventCountry "URS"]
 [FEN ""]

 1. Nf3 Nf6 2. g3 e6 3. Bg2 Be7 4. O-O O-O 5. c4 d5 6. d4 c6 7. Qc2 b6 8. Rd1 Nbd7 9. b3 Bb7 10. Nc3 Rc8 11. e4 dxe4 12. Nxe4 Nxe4 13. Qxe4 Qc7 14. Bf4 Bd6 15. Bxd6 Qxd6 16. c5 Qe7 (16... bxc5? 17. dxc5 Nxc5? {This makes it worse} 18. Qb4 Qe7 19. Rdc1 $18) 17. b4 Rfd8 18. Qc2 Nf6 19.Ne5 Nd5 20. a3 b5 21. Be4 g6 22. h4 a5 23. bxa5 Ra8 24. a4 b4 25. Bxd5 Rxd5 26. Rab1 f6 27. Ng4 Rad8 28. Rxb4 Bc8 29. Ne3 R5d7 30. Rb8 e5 31. d5 cxd5 32. c6 Rd6 33. c7 Rf8 34. Rxd5 f5 35. Qc5 Re6 36. Qxe7 Rxe7 37. Rxc8 Rxc8 38. Rd8+ Re8 39. Rxe8+ Rxe8 40. Nd5 1-0


text:
Carlsen vs. Nepo this morning, why didn't Nepo win the pawn?
On move 19 Carlsen played Nd5. Why didn't Nepo win the pawn with Nxd5? If Bx, then Qxb4, or if px, then Qxb4 attacks the Bc4 still and Bxa6 then Nc5 and move the rook.
 [FEN ""]
 [Event "Tata Steel Rapid & Blitz"]
 [Site "Kolkata"]
 [Date "2019.11.22"]
 [Round "2.3"]
 [White "Carlsen, Magnus"]
 [Black "Nepomniachtchi, Ian"]
 [Result "1-0"]
 [ECO "B51"]
 [WhiteElo "2870"]
 [BlackElo "2773"]
 [PlyCount "87"]
 [EventDate "2019.??.??"]
 [EventType "blitz"]
 [WhiteTeam "Norway"]
 [BlackTeam "Russia"]
 [WhiteTeamCountry "NOR"]
 [BlackTeamCountry "RUS"]

  1. e4 c5 2. Nf3 d6 3. Bb5+ Nd7 4. d4 cxd4 5. Qxd4 a6 6. Be2 Ngf6 7. O-O e5 8. Qe3 Nc5 9. Nfd2 b5 10. c4 bxc4 11. Nc3 Bb7 12. Bxc4 Be7 13. b4 13... Ne6 14. Nb3 Rc8 15. Na5 Qd7 16. Qd3 O-O 17. Be3 Bd8 18. Nxb7 Qxb7 19. Nd5 Nc7 20. Nxf6+ Bxf6 21. Rab1 Rfd8 22. Rfd1 h6 23. f3 Qc6 24. Qb3 Qe8 25. a4 Rb8 26. b5 axb5 27. axb5 Ne6 28. b6 Bg5 29. Bf2 Nd4 30. Bxd4 exd4 31. Rxd4 Rdc8 32. b7 Rc5 33. Bd5 Qe7 34. Rc4 Qc7 35. Rxc5 dxc5 36. g3 Bf6 37. Kg2 Qe7 38. Qb6 Be5 39. Qc6 Kh7 40. f4 Bd4 41. Qc8 Qd6 42. Qf5+ Kh8 43. Kh3 Qa6 44. e5 1-0

The solution to that is much easier than it looks, and a fairly common type of position in practical play. After 19.Nd5! taking the nice outpost square, if black responds with 19…Nd5 then white can simply play 20.Bd5 Qb4, then Qxa6 just leaves black positionally lost despite even material. In positions like that where you have a rook behind the a-pawn, and the bishops both pointing at the queenside, the pawn on a2 is going to run fast and hard, and soon cost black heavy material.
  [FEN ""]

  1. e4 c5 2. Nf3 d6 3. Bb5+ Nd7 4. d4 cxd4 5. Qxd4 a6 6. Be2 Ngf6 7. O-O e5 8. Qe3 Nc5 9. Nfd2 b5 10. c4 bxc4 11. Nc3 Bb7 12. Bxc4 Be7 13. b4 13... Ne6 14. Nb3 Rc8 15. Na5 Qd7 16. Qd3 O-O 17. Be3 Bd8 18. Nxb7 Qxb7 19. Nd5 Nxd5? 20. Bxd5 Qxb4 21. Qxa6 {And from here, it is easy to see what kind of troubles black has.}

Thank you @Phishmaster. I really like your answers.

After 1...Nxd5 2.Bxd5 Qxb4 3.Qxa6 White has a clear advantage. He has two very nice bishops and an outside passed pawn on the a-file. Black's d6-pawn is a clear weakness, his bishop on d8 lacks prospects, and the list goes on.
However, Stockfish actually gives 1...Nxd5 as its top choice, with 1...Nc7 coming in as a close second. In either case though, it says White is better by roughly a pawn and a half.


text:
Why have engines not increased top rated chess players' Elo?
The arrival of strong chess engines as Stockfish, Houdini or Rybka allow top players to deeply prepare lines in openings or to study better endgames.
I would expect a rating increase of top players. However, Kasparov's top score from 1999 is still the second best rating score of all time and Karpov and Fischer are still in the top twenty historical rated players.

Source: Wikipedia
If those engines have a 3600 Elo, shouldn't top players have profited from it to leave Kasparov's 2851 score in 1999 far away?
And shouldn't more than 18 players surpass Fischer's 2785 in 1972?

I think they certainly have increased their ELO, but more importantly, their overall chess strength. ELO is only a rating relative to others in the pool so it may tend to go up more slowly if everyone in the pool gets better, which they have collectively.
First, you need to take an average of the top players, rather than look at just two incredibly special players, Kasparov, and Carlsen, and their peak ratings. Fischer was a total anomaly for his time, and again, you cannot base a lot on one person. Humans probably have a limit mentally much the way runners will eventually hit a speed wall that they cannot break. It is the Bell Curve in action: Easy to make progress in the middle, but harder on the end.
ChessBase, and the first strong engine, KnightStalker (aka Fritz 1.0, renamed at version 2.0) came out in 1990, and the Internet was still in its infancy. In January of 1990, there were only two players over 2700, Karpov at 2730, and Kasparov at 2800. Today, there are 37 players over 2700, and of those, three are over 2800.
I have been playing for a long time, and anyone, who knows my handle, has seen me watching relays of the top tournaments on ICC for more than 20 years, and I can say that it is not just inflation from having actually watched the level of play improve over the years. Players at the Master-level, including even normal Masters, are MUCH better now due to the tools available today than the tools available when I first became a Master.
When I first started playing, all we had was books, and a local club. Today, I can logon virtually any day, and play a GM. I was also a ranked tennis player as a teenager, and I can tell you from that experience, playing better competition makes you better, so being able to logon and play stronger players than ever has increased the overall level of play. In addition, we now have ChessBase, and a database of about 8.3M games that can be sorted efficiently and studied. We also have engines, as noted in the question, and they certainly have also added to our chess knowledge, and fundamentally changed how the top players prepare. Lastly, I mentioned books, and as an avid collector (I had 1800 at my peak), I can tell you that even the quality of the material in books is on another level since when I started.
I cannot tell you what proportion of all these advances have played toward X-number of rating points increase, but I can tell you that without a doubt, they all have lead to players at the top levels, and even down some, being much better overall.

The question is apparently based on a misunderstanding of how ELO ratings work. There is absolutely no mechanism by which the overall increase in players' strength would lead to increase in their ELO. The actual value of the ELO rating bears no meaning; nor does the comparison of ELO at distant times. The only thing that has direct relevance is the difference in simultaneous rating between players.
If tomorrow FIDE decided to add a constant, say, 500 points, to every player's rating, essentially nothing would change - the outcomes of games would lead to the same increments in ratings, so the rating dynamics would be the same, just at +500 points level. And the computers will provide no basepoint - their ELO is relative to human players, so they will play at 3600 rather than 3100.
The same applies if such a constant were somehow added or subtracted gradually due to natural processes - e. g., expansion of rated players' base, players becoming inactive with higher rating than they started with, etc. And this, apparently, did happen as we witnessed rating inflation until recently.
Similarly, if all the players suddenly, or gradually, start playing stronger, without a change of their relative strength, there is no reason to expect a change in rating dynamics.

If those engines have a 3600 Elo, shouldn't top players have profited from it to leave Kasparov's 2851 score in 1999 far away?

No. The main effect of engines and also the internet has been to democratise chess. The top players have always had access to top level evaluation and knowledge. For lower level players that kind of knowledge, analysis, position evaluation, endgame knowledge was very difficult to acquire.
This is important because higher level players gain rating points by beating lower level players. If those lower level players are harder to beat because of increased access to the analysis and knowledge that engines and the internet provide then it actually becomes harder to reach higher levels as measured by rating.

A few things:
1) Ratings overall tend to rise due to inflation of more players entering the pool, rather than the average playing strength of players increasing. If everyone becomes better by some factor due to engines, why would top players' ratings increase? They're now playing opponents who have also gotten stronger by roughly the same amount.
2) Kasparov, Karpov, and Fischer are anomalies of a sort (Kasparov especially), considering they are all world champions. And still, they only occupy 3/20 spots on the list - all other ratings were achieved in the modern era.
3) Engines are making people stronger, but not to a huge extent. People aren't able to extract all the strength out of an engine, we just see the moves it recommends.
In summary, engines make people somewhat stronger, but in any case this wouldn't be reflected in the ratings. The pool of players is a closed system: everyone getting stronger doesn't benefit one player/group of players in particular. The way the ratings rise (at all levels) is from more people joining the system.
EDIT: one way you would see some increase purely due to engines is in a hypothetical scenario where we played against another group of people who didn't have access to our engines.
EDIT 2: Point 1 may not be entirely correct (see the discussion in the comments).

That's a common misconception: pure ELO rating actually deflates due to new players entering the pool. They enter at low rating, then progress, taking the points away from the others. As they become inactive,  a vast majority of players are higher rated than at entry. This means they take points away from the system.

@Kostya_I But new players bring more points into the system via their initial rating. Even if one's starting rating is only 1000, they still brought 1000 points in by basically taking nothing away.

@Inertial_Ignorance, imagine a new player who gets initial rating of 1000 points and never plays again. By your logic, he or she "brought 1000 points in", but in fact nothing changed for other players. And if they do play, they will typically progress - say, to 1500. That's 500 points taken away from other players, so, their rating will decrease by that amount  while their strength has not diminished. That's deflation. Of course, someone could drop below their inital level, which is the only case they really "bring points in", but that's a rare case

@Kostya_I That's a good point. But inflation is happening with ratings, so how do you explain that?

@Inertial_Ignorance, the inflation is no longer happening - the top-N averages are steady for about 7-10 years. The inflation in 1990s and 2000s might have been due to lowering the rating floor, where a lot of established players were added, who no longer progressed from that point on, but aged and declined in strength, giving away the rating points. Or it may be that the deflation counter-measures (different coefficient K for new players) were not properly adjusted.

People are not computers.  They learn and memorize as much as possible but they can not do as much as a computer can nor as fast.  The top players are doing everything they can but they can not do it all like the computer does.

Well I think Carlsen has sometimes played a 25 moves Stockfish line that wasn't on books. I agree with your answer and it gives a point but I was not asking why GM don't reach engines level, I was asking why they don't increase a bit more his rating, saying all top ten players at 2900.

I suspect that all the top players are using as much as they can whether printed or online to improve.  So if nobody improves more than the others and they only keep playing themselves then their ratings will stay the same.  The top GMs need to play wider competition and take some of their points from lower rated players  for the top to improve.

That's the point of my question. Allbody have engines, but top rated players may prepare better games than said, the 2600. Caruana says his point is game preparation. Doesn't engines help 2800 to beat lazy 2600 more easy than Bobby, Gary or Anatoly faced to?

Maybe, but that won't affect the ratings.


text:
In the Dutch Defense, why does white play b3 and Ba3?
In the Stonewall Dutch Defense, why does white play b3 and Ba3? Should I try to avoid it, or does it not matter?
[fen ""]

1. Nf3 e6 2. d4 f5 3. g3 Nf6 4. Bg2 d5 5. O-O Bd6 6. b3 O-O 7. c4 c6 8. Ba3

The main reason is to exchange black's good bishop, and what would probably end up being white's bad bishop after a later e3. Another common way of doing this is Bg5xNf6. This also highlights black's dark-square weakness problem that he will have to watch out for for quite a while.
This exchange on a3 leaves black's other bad bishop on c8 more markedly bad, and the e5 square more weakened. After the exchange on a3, black can, and usually should, gain a tempo with Qe7, and the white Na3 will redirect to Nc2-e1-d4 (or sometimes via Nc2-b4-d3) to further control e5.
This scores well in my database at 67% for white, but many of the games are between players of disparate ratings. At the higher levels, it seems that black can hold equality, so I would say that if you are stronger, there is no need to avoid it, but if you are weaker against a good positional player, you might want to try to get in Qe7 earlier to make Ba3 harder, but white still has a4 then. I am not sure you can really, and totally avoid it if that is the plan white chooses.

Thank you Phishmaster..

I hope this helped you.

Thanks for trying. I am not sure what the trigger I missed was, but I did not get that final hat. I appreciate it.

In the pawn structure of the Stonewall Dutch the light squared bishop is the sick piece in black's position and the dark squared bishop is the star. If white can exchange the dark squared bishops then white already stands much better because of all the resulting weak dark squares in black's position, particularly e5.
Consequently it is a mistake for black to reply to 6. b3 with O-O allowing Ba3. Essential is Qe7 to prevent Ba3 and the subsequent trade of black's best piece. An early b6 is probably also important for black to allow the plan of a4 followed by Ba3 anyway by white to be answered by c5 blocking the exchange, possibly with Nbd7 to reinforce c5.

I don't know that I would call it a "mistake". The game I referenced, black was GM Francisco Vallejo Pons, who peaked at 2724. I doubt he would make a mistake on move 6. Besides, white can still force it with a4 and then Ba3. It is just a game as we say.

Thank you also Brian.

When you look at the position, you see a horrible light Bishop for Black, and you see a dark Bishop for White that doesn't have a whole lot to do, effectively. It's biting on the d-pawn, its 'natural prey' (the Black Knight on f6) cannot be effectively pinned, as the queen will be wanting to slide to e8 in this position anyway, so what's it going to do?
The idea of trying to force the exchange of Black's dark Bishop by effectively pinning it against the Rook is very attractive. It's more effective against the old stonewall lines, when the Bishop is on e7, because in this line Black can, effectively, get a free Queen move in by moving it to e7, forcing White into spending another tempo to achieve the aim.
It's a worthy aim, simply because of how mind-achingly bad Black's other Bishop is. But it's not a winning aim. Black can get some free development playing off the misplaced Knight on a3, and where's it going to go? It can't meaningfully get to b5, or really even c4. Back home to b1 or c2 aren't really attractive, and the only other choices are something like Qc1 or letting go of the tension in the center with c5. (It should be noted that the central tension is one of White's weapons against Black's buildup for a wing attack, so dropping it is kind of a big thing; I've been known to try and tease White into doing that with ...Qd6 simply because of how much stronger that makes an eventual ...e5. Depends on how you feel about double-edged positions whether you'll like that idea. White can get an interesting steamroller going on the Queenside if Black isn't paying attention.)
The best thing I can say for it is it can be effective against a lot of Dutch players who haven't spent time thinking the unthinkable: How do they attack without their chief weapon, the Kingside Bishop? Having to answer that question can throw a lot of Stonewall players off their game.
On the other hand, it does relieve one of the major issues with the Dutch, which is that Black has one more minor piece than they have room for, and that extra space can be handy as the pieces roll out. If Black has learned to be flexible, their game still has a lot of play in it (one reason why this isn't seen more often in high-end play).
If you're looking for a good anti-Dutch line, I've always felt the lines based around Nh3/Bf4 offer more than the b3/Ba3 ones. YMMV.


text:
Why was 20.Qe3 so good in Botvinnik-Sorokin?
Why was 20.Qe3 so good in Botvinnik-Sorokin?
It doubles the pawns, and doesn’t do much else.

First of all, it was played by Botvinnik, a strong World Champion, and one of the most logical players ever, so it clearly has to do more than just let black ruin the white pawns.
It does many things:

It trades off black’s best piece, the active Qc5, and it cannot be
avoided with Qc7? Nxe5!. Trading your opponent's active pieces is very desirable, and I suspect this was the primary motivation for Botvinnik even looking at Qe3.
Despite the fact that those pawns have been weakened, they control
many critical squares. They are also very hard to get at, so
although they may matter in the endgame, black cannot attack them
anytime soon, and other factors will be much more important.
This is a principle that is not seen often, and often missed by
weaker players, but sometimes when you trade down material when attacking,
particularly, trading off a good defender, it allows the remaining pieces to
strengthen, and they become unopposed. In this case, the doubled
rooks are now monsters, and white’s significant lead in development
is going to show even more.
How does black develop the Bc8? In the game, he chose g4 but soon
actually had to strengthen white’s pawns after all.
Lastly, black is going to have a hard time defending e5, and it is
attacked immediately.

The minor weakness, that black can't even get near, was nothing compared to the weaknesses that were exposed when the black queen was no longer on the board to defend them. In short, the Qc5 was the glue that held the black position together, and without it, there was no defense.
 [FEN ""]
 [Event "URS-ch07 Final"]
 [Site "Moscow"]
 [Date "1931.10.25"]
 [Round "2"]
 [White "Botvinnik, Mikhail Moisevich"]
 [Black "Sorokin, Nikolay Tikhovich"]
 [Result "1-0"]
 [ECO "D60"]

 1. d4 d5 2. Nf3 Nf6 3. c4 e6 4. Nc3 Nbd7 5. Bg5 Be7 6. e3 O-O 7. Bd3 c6 8. O-O a6 9. a4 dxc4 10. Bxc4 c5 11. dxc5 Bxc5 12. Qe2 h6 13. Bh4 Be7 14. Rfd1 Nh5 15. Bxe7 Qxe7 16. Rd2 Nb6 17. Rad1 Qc5 18. Ba2 Nf6 19. e4 e5 20. Qe3 Qxe3 (20...Qc7? 21. Nxe5!) 21. fxe3 Bg4 22. a5 Nc8 23. Rc1 Bxf3 24. gxf3 Ne7 25. Nd5 Nc6 26. Nxf6+ gxf6 27. Rd7 Rab8 28. Kf2 Nxa5 29. Rcc7 Rbc8 30. Rxf7 Rxc7 31. Rxc7+ Kh8 32. Bd5 b5 33. b3 Rd8 34. Kg3 f5 35. Kh4 fxe4 36. fxe4 Rd6 37. Kh5 Rf6 38. h3 Rd6 39. h4 Rb6 40. Kg4 Rf6 41. Ra7 Rb6 42. Re7 Rd6 43. Rc7 Rf6 44. Ra7 Rb6 45. Rc7 Rf6 46. Kh5 Rd6 47. Bf7 Rf6 48. Bg6 Nxb3 49. Kxh6 Rf8 50. Rh7+ Kg8 51. Rg7+ Kh8 52. Bf7 Rxf7 53. Rxf7 Kg8 54. Kg6 Nd2 55. Rd7 1-0

Phishmaster your answers are really great. Thanks man.

Glad to help, and  thanks for accepting my answers today. I love answering real chess questions the best, meaning about positions, so keep them coming, and I will probably reply within a few hours most times.

Move 20.Qe3? is actually very weak and misses the win. The winning move was 20.Rd6!
This was all known more than 10 years ago - https://chesspro.ru/card_index/smoktiy_

Link only answers without context aren't exactly good, given links can do, which this one seems to have.


text:
Why are there no more adjournments?
I keep reading about adjournments in books, but why don't we use them anymore? They seem like cool analysis sessions.

I only had a few adjournments in my tournament career.  I enjoyed staying up late with my friends analyzing.  One time I set up the position wrong and analyzed incorrectly all night.

Primarily because computers have rendered adjournments obsolete. In addition, with the advent of digital clocks with delay or increment, it is much more fair to have people play it out over the board. It is much better to have the players decide it than having a team of people helping them overnight, or nowadays, a strong computer.

Adjournments are still used but very rarely.
They are deprecated and this is shown by the path that the FIDE Laws of Chess have taken over the years in prescribing their use.In the previous incarnation of the laws they were covered in an appendix. In versions before that in the main body. In the discussions preceding the release of the current rules there was a move to remove them but the English Chess Federation argued in favour of retaining them for one more cycle because there was at least one league in London which still used them.
The compromise was that a new section was created in the Laws after the appendices called "Guidelines". The rules governing adjournments were moved to "Guidelines 1". This section is scheduled for retirement in the next release of the rules unless the ECF successfully petition for a further extension.
"Guidelines 3" covers quickplay finishes which is also destined for the dustbin. Both practices made sense before the advent of digital clocks and the use of increment/delay but really have no place in the 21st century because both practices introduce an element of avoidable unfairness. In the age of engines any adjourned game is going to be decided by the engine not the imagination, wit, ability and knowledge of the two players.
Since (fingers crossed) this section is likely to disappear from the rules soon and isn't too long it is perhaps worth reproducing:

Guidelines I. Adjourned games
I.1.1 If a game is not finished at the end of the time prescribed for
  play, the arbiter shall require the player having the move to ‘seal’
  that move. The player must write his move in unambiguous notation on
  his scoresheet, put his scoresheet and that of his opponent in an
  envelope, seal the envelope and only then stop the chessclock. Until
  he has stopped the chessclock the player retains the right to change
  his sealed move. If, after being told by the arbiter to seal his move,
  the player makes a move on the chessboard he must write that same move
  on his scoresheet as his sealed move.
I.1.2 A player having the move who adjourns the game before the end of
  the playing session shall be considered to have sealed at the nominal
  time for the end of the session, and his remaining time shall so be
  recorded.
I.2. The following shall be indicated upon the envelope:
I.2.1 the names of the players,
I.2.2 the position immediately before the sealed move,
I.2.3 the time used by each player,
I.2.4 the name of the player who has sealed the move,
I.2.5 the number of the sealed move,
I.2.6 the offer of a draw, if the proposal is current,
I.2.7 the date, time and venue of resumption of play.
I.3 The arbiter shall check the accuracy of the information on the
  envelope and is responsible for its safekeeping.
I.4 If a player proposes a draw after his opponent has sealed his
  move, the offer is valid until the opponent has accepted it or
  rejected it as in Article 9.1.
I.5 Before the game is to be resumed, the position immediately before
  the sealed move shall be set up on the chessboard, and the times used
  by each player when the game was adjourned shall be indicated on the
  clocks.
I.6 If prior to the resumption the game is agreed drawn, or if one of
  the players notifies the arbiter that he resigns, the game is
  concluded.
I.7 The envelope shall be opened only when the player who must reply
  to the sealed move is present.
I.8 Except in the cases mentioned in Articles 5, 6.9, 9.6 and 9.7, the
  game is lost by a player whose recording of his sealed move:
I.8.1 is ambiguous, or
I.8.2 is recorded in such a way that its true significance is
  impossible to establish, or
I.8.3 is illegal.
I.9 If, at the agreed resumption time:
I.9.1 the player having to reply to the sealed move is present, the
  envelope is opened, the sealed move is made on the chessboard and his
  clock is started,
I.9.2 the player having to reply to the sealed move is not present,
  his clock shall be started; on his arrival, he may stop his clock and
  summon the arbiter; the envelope is then opened and the sealed move is
  made on the chessboard; his clock is then restarted,
I.9.3 the player who sealed the move is not present, his opponent has
  the right to record his reply on the scoresheet, seal his scoresheet
  in a fresh envelope, stop his clock and start the absent player’s
  clock instead of making his reply in the normal manner; if so, the
  envelope shall be handed to the arbiter for safekeeping and opened on
  the absent player’s arrival.
I.10 Any player who arrives at the chessboard after the default time
  shall lose the game unless the arbiter decides otherwise. However, if
  the sealed move resulted in the conclusion of the game, that
  conclusion shall still apply.
I.11 If the regulations of an event specify that the default time is
  not zero, the following shall apply: If neither player is present
  initially, the player who has to reply to the sealed move shall lose
  all the time that elapses until he arrives, unless the regulations of
  an event specify or the arbiter decides otherwise.
I.12.1 If the envelope containing the sealed move is missing, the game
  shall continue from the adjourned position, with the clock times
  recorded at the time of adjournment. If the time used by each player
  cannot be re-established, the arbiter shall set the clocks. The player
  who sealed the move shall make the move he states he sealed on the
  chessboard.
I.12.2 If it is impossible to re-establish the position, the game
  shall be annulled and a new game shall be played.
I.13 If, upon resumption of the game, either player points out before
  making his first move that the time used has been incorrectly
  indicated on either clock, the error must be corrected. If the error
  is not then established the game shall continue without correction
  unless the arbiter decides otherwise.
I.14 The duration of each resumption session shall be controlled by
  the arbiter’s timepiece. The starting time shall be announced in
  advance.

The question doesn't indicate what context it's being asked in, but at least in the US (in USCF events), adjournments are generally not used because most tournaments are played using sudden-death time controls.  This makes it easy to predict (at least approximately) when a round will end, because a player can't get an additional time period by completing a certain number of moves.  Once the time period expires in a sudden-death time control, the game is over, regardless of how many moves have been made.


text:
Are there women only tournaments for lower rated players?
Are there women only tournaments for lower rated players? There are many for top women, but not for me.
I can't seem to find any, but it would be fun. Can anyone help?

It may depend on your location, but such tournaments do exist.
For example, the 2019 Texas Women's Chess Championship had some low-rated players. The 2019 Wisconsin Junior Open had a females-only section, with any female juniors from Wisconsin eligible to play in it, regardless of rating.
Upcoming, the U.S. Women’s Open will be in June in Las Vegas, and seeing as how there are U1400 prizes, it clearly isn't just for elite players.

There is not that much demand.  Tournaments are money making efforts for the sponsors.
If you want to play at a low level then just enter an open section limited to the rating you can play at.  Many tournaments have lower rated sections that go way down in ratings,  some only have two sections  and some may only have one due to small amount of people expected.
NOTE that your chances are bigger of finding one as the tournament size increases. Clearly the best would be at national tournaments followed by large regional ones.  Then large major cities and possibly may also some selected states.
USCF magazine should list all tournaments with the section ratings they offer.


text:
Recommendations for kids sites
I am a teacher, and don’t really play much. My students like chess and I want to send them to some safe chess sites for kids. Recommendations?

I have a few.
Chess Kid is part of chess.com, which is the largest chess site in the world. There are both free and paid memberships.
Another great site is ChessKids Academy. They have come very basic lessons for newcomers, and the best thing is that it is free.
Kid Chess also has some nice material that is free.
All of these sites have components for both the players, and the adults, who are helping them.


text:
Why 4... Nxb4 is not played in Evans gambit?
4... Nxb4 is never played on chesstempo database for +2200 players games, being Bxb4 the most popular move.

I don't find any significant change after capturing the pawn with the knight unless after 5. c3, black can play Na6 supporting an eventual c5 to block the a3-f8 diagonal.
If 5...Nc6 it looks the same position as 4...Bxb4 5. c3 Bc5
Stockfish evaluates 4... Nxb4 as =:

Why doesn't this move appear on databases is what I am wondering.

It comes down to flexibility. In most cases, Nb4 will end up in the same position, as you said, but Bb4 give you at least two more common alternatives, and a couple less common ones.
 [FEN ""]

 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Nb4 5. c3 Nc6 (5...Na6?) 6. d4 exd4 7. cxd4

Compare this with this line where black can play Ba5, Be7, Bc5, and even Bd6 have been played a fair amount of times. It is, generally, favorable to make your opponent worry about more options.
 [FEN ""]

 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bb4 5. c3

Is 5....Na6 so bad? As white I use to profit the a3-f8 diagonal if black bishop goes to b6 and Na6 supports c5

I think just attached the ? by sight since the N does nothing for anything on a6. After plugging it in to Stockfish, it agrees totally as 6.Nxe5 is +1.81 after Qg5 7. d4 Qg2 8. Rf1 and it is really bad.

Oo yup dismised 6.Nxe5 is free thx

But not so simply to play after 6....Qe7 at my level on blitz. It is a funny gambit :)

That is even much worse after d4, and f7 cannot be defended

Yup. But there are some lines were black sacrifies f7 and h8 rock. I think they are all bad, but blitz is blitz, sometimes the gambit becomes funny for black :)

It is already over +3 for white there, and the only move is Nf6; Bf7 Kf8; Bb3, and there is nothing there that will convince me that is fun to play for black. You cannot even dislodge the Ne5 with d6 f4! since taking you cannot move the N due to 0-0 winning.

But the knigth at a6 should not help the counteratack. Sorry for not checking it was a +2 position

In my database it actually appears in 131 games, or roughly 1.5%.
The move also isn't objectively bad. But it's unpopular partly because it unnecessarily limits Black's options. After 4...Nxb4 5.c3, Black is practically forced to play 5...Nc6, which transposes to 4...Bxb4 5.c3 Bc5 (as you mentioned). Meanwhile, after 4...Bxb4 5.c3, Black has many options (5...Ba5, 5...Be7, 5...Bd6, or 5...Bc5).
There's also the issue that 4...Nxb4 looks unnatural. The knight should generally stay on c6 where it guards the key centre squares e5 and d4. Finally, some people might think allowing 5.Nxe5 is much better for White, even though it actually gives Black a winning advantage after 5...Qf6!.

Isn't this basically exactly what I said in my answer and the comments with the exception of quoting the stats?

@PhishMaster I also mentioned stats, the knight staying on c6 to guard squares, and the issue of some people thinking 5.Nxe5 is good for White. I didn't copy your answer when writing mine.

Even if you did not intend to, you still did. Your main idea is almost word for word what I wrote.  You should read the other answers before answering. The comments to the other answer also go over Ne5? in depth. It was not cool at all.

@PhishMaster I don't see how my main idea is word for word whatsoever, please point out which sentence you're referring to. If you mean the 5th moves I mentioned for Black, I found them by looking at the top choices in a correspondence database. I mentioned Ne5 because at first I thought it was good, and A. N. Other also thought it was best. ...Qf6 was found immediately with my engine, not by using your comment.

I wrote that quickly at night on a phone: I should have said idea for idea ("limits black's options="flexibility"; "(5...Ba5, 5...Be7, 5...Bd6, or 5...Bc5)"="Compare this with this line where black can play Ba5, Be7, Bc5, and even Bd6 have been played a fair amount of times."; and "5.Nxe5 is much better for White, even though it actually gives Black a winning advantage after 5...Qf6!."=the comments "That just loses to Qf6 since the Ne5, Qf2 mate, and the Ra1 all hang. The best line then is 6. 0-0 Qe5 7. c3 Bd6 8. g3 (f4 Qc5+ and Bc4 hangs) Nc6 and keeps the piece." Still, looks too close.

@PhishMaster Literally the only thing your answer touched on was flexibility, and there we have similar ideas. I mentioned 5.Nxe5 as a faulty reason some people playing Black don't choose 4...Nxb4: you never mentioned this as a reason, you only gave an engine line in the comments showing why it's wrong. That wasn't part of your answer explaining the difference in popularity between 4...Nxb4 and 4...Bxb4. In addition, I also mentioned stats and how 4...Nxb4 looks unnatural. The only idea actually part of your answer to the OP's question that we share is limiting options.

After 4...Nxb4 5.Nxe5 looks like a very strong reply, gaining the important e5 Pawn almost for free and posing an immediate threat to f7.

That just loses to Qf6 since the Ne5, Qf2 mate, and the Ra1 all hang. The best line then is 6. 0-0 Qe5 7. c3 Bd6 8. g3 (f4 Qc5+ and Bc4 hangs) Nc6 and keeps the piece.

P.S. I am not one of the people, who downvoted since I just assumed you would delete this answer.

No worries. I never thought you downvoted my answer, but you can do that, if you feel so. I’ll keep it as a reminder of how easy it is to make a mistake. I didn’t see 5...Qf6. As simple as thay.

I still rarely downvote an answer, and still have not for this one.

It seems that 4...Nxb4 might be an option in view of the "trap" 5.Nxe5 Qf6. Of course after 5.c3 Nc6 Black is committed to the ...Bc5 line. At this point, I'd play 5.0-0 as White, rather than 5.c3.