Space is the total amount one controls with his pawns and pieces. The advancement of pawns creates weak squares but also space.
White has 14 weak squares but black cannot exploit them. White has a significant space advantage.
White's advanced pawns give him control on the kingside and in the center.
An outpost is a square in the opponent's territory that is weak, is defended by a friendly pawn, and can be occupied by a piece.
Black's last move, 11...e5 created a white outpost on d5. The idea was to prevent white from playing e5, getting space and creating a threat but black must play with accuracy or white will exploit the outpost.
Black did not play with accuracy. White has a strong outposted knight, thus he has a significant advantage.
An semi-outpost is a square in one's own territory that cannot be attacked by enemy pawns, is defended by a friendly pawn, and can be occupied by a piece.
Black's f5-knight occupies a semi-outpost. White's d6-rook occupies an outpost.
A quasi-outpost is a square in the opponent's territory that is weak and can be occupied by a piece.
Black's c4-knight occupies a quasi-outpost.
An pseudo-outpost is a square in the opponent's territory that isn't weak but whose defense would create weak squares.
White's d5-knight is a pseudo-outpost because black can attack it with ...e6 but that would weaken the d6-square.
An isolated pawn is one with no friendly pawns on adjacent files.
White played 1.c4 because he was worried about black's kingside pawn storm. After 1...d-captures-c4 black has the advantage because white's isolated d4-pawn is a long-term vulnerability.
Black is in complete control; the isolated d4-pawn is blockaded and can be threatened.
An unsheltered isolated pawn is one with no enemy pawn in front it.
White's unsheltered isolated d4-pawn can be attacked vertically.
A sheltered isolated pawn is one with an enemy pawn in front it.
White's sheltered isolated e3-pawn is safe from vertical attacks.
An isolated pawn can offer compensation in the form of space.
White's pieces are placed well; his knights are on pseudo-outposts and his rooks are on deep, open files.
White's pieces are placed well: his knight is on a pseudo-outpost and his c3-rook has options on the third rank.
A backward pawn is one that cannot be defended by friendly pawns because its advance is impeded.
Black cannot advance the backward d6-pawn because white controls the d5-square.
White will win the backward d6-pawn.
An unsheltered backward pawn is one with no enemy pawn in front it.
Black's unsheltered backward e6-pawn can be attacked vertically. It cannot advance because white will win the d5-pawn.
A sheltered backward pawn is one with an enemy pawn in front it.
The backward pawns are sheltered and cannot be attacked vertically.
The backward pawns are being attacked laterally and diagonally.
A backward pawn can offer compensation in the form of space.
Black has created a backward d6-pawn.
The backward d6-pawn gives black central control and a good c8-bishop.
Black has space in the center and on the queenside; black has a significant advantage.
An overextended pawn is one that is difficult to defend because it is close to the enemy's forces.
White's e4- and f4-pawn duo looks healthy but black will attack it.
24...Knight-e6 Black threatens the f-pawn. 25.f5 Knight-d4 Black threatens the f-pawn. 26.f6 g-captures-f6 27.e-captures-f6 White's f-pawn is overextended and vulnerable.
Overextended pawns make targets and potential duels.
White's g4-, f5-, and d5-pawns are overextended.
Black has used white's overextended pawns to create an semi-open file against white's isolated h-pawn. White's f5- and d5-pawns are overextended.
Pawns that are well protected are not overextended.
Black's d4- and c3-pawns are well protected.
There is a difference between a strong pawn and an overextended pawn.
Identification can be difficult in some situations.
If 29.Knight-d3 e-captures-f5 30.g-captures-f5 Knight-c6 black has an advantage because he is blockading the passed c5-pawn and he has a queenside majority.29.c6 White threatens c7 with the double threat of c8=Queen and c-captures-b8=Queen 29...King-d6 30.f-captures-e6 White threatens e7 ...King-captures-e7 c7 31...Knight-captures-c6 32.Knight-captures-c6 King-captures-c6 Is white's e6-pawn strong or overextended?
After 32.e4 d-captures-e4 33.d5-check white's pawns are strong because they cannot be captured. If King-captures-d5 then e7 wins.
The pawns are strong; black resigned.