Nimzo-Indian Defense: Classical Variation, Zurich Variation

The opening move 1.d4 is a standard opening move for white in chess. It's a part of the Queen Pawn Openings where white controls the central squares d4 and e4. The idea of playing d4 is to control the center and develop the pieces quickly. By moving the pawn to d4, white prepares to place a pawn on e4, which controls an even bigger space in the center. The pawn on d4 also helps control the c5 square. The move d4 is a crucial move to start an aggressive and attacking game.

The move Nf6 by Black is a response that mirrors White's d4. This move helps Black to control the central squares and develop the knight. By placing the knight on f6, Black attacks the pawn on d4 and also prepares to play e5. The knight on f6 also helps to control the e4 square, limiting the options for White's pieces to move there. In sum, Black's move Nf6 is an effective strategy to counter White's control of the center and prepares for attacking play.

White's move c4 after 1.d4 Nf6 is known as the Queen's Pawn Opening, and is one of the most popular chess openings. This move further expands White's control of the center and prepares for the development of the knight on c3. By playing c4, White also threatens to take control of the d5 square and create a pawn chain from a2 to d5. Additionally, the pawn on c4 guards the d5 square, which would otherwise be a potential square for the black knight to jump to. In sum, the move c4 is a strong start to an attacking game for White.

In the Nimzo-Indian Defense: Classical Variation, Zurich Variation, Black plays e6 after 1.d4 Nf6 2.c4. The move e6 helps control the square d5 and also prepares the development of the bishop. After placing the pawn on e6, Black also prepares to break the pawn chain on c4 by playing either c5 or d5. Additionally, the pawn on e6 helps prevent the white knight on c3 from moving to the d5 square. In sum, the move e6 is an essential part of Black's plan to counter White's control of the center and prepare for attacking chances.

White's move Nc3 after 1.d4 Nf6 2.c4 e6 is an essential move to control the center and develop the knight. The knight on c3 also prepares to support the pawn on d4 and creates a threat on the d5 square. By playing Nc3, White also increases the pressure on Black's e6 pawn. Additionally, this move prepares the way for moving the dark-squared bishop to the squares b5 or d3. In sum, the move Nc3 helps White to further develop their pieces and establish control over the center of the board.

Black's move Bb4 after 1.d4 Nf6 2.c4 e6 3.Nc3 is called the Nimzo-Indian Defense, and it helps to attack and trade the white knight on c3. This move also attacks the pawn on d4 and gains control of the d4 square. By playing Bb4, Black also prepares to castle kingside and develops a key piece. Additionally, this move can pressure White to make a move like a3 or Bd2, further delaying the development of the white kingside. In sum, the move Bb4 is a vital part of Black's strategy to put pressure on White and create opportunities for an attacking game.

In the Nimzo-Indian Defense: Classical Variation, Zurich Variation, White plays Qc2 after 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4. The move Qc2 helps White to control the d3 square and prepares for castling kingside. By playing Qc2, White also prepares to advance the e4 pawn and gain further control of the center of the board. This move also helps the queen to be in a safer position and avoids any potential tactics from Black's bishop on b4. Additionally, this move prevents the black knight on d7 from moving to the c5 square, further limiting Black's options. In sum, the move Qc2 is a useful part of White's strategy to develop their pieces, protect their king, and control the center of the board.

Black's move Nc6 after 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Qc2 is a crucial part of their plan to control the center and develop their pieces. This move also attacks the white pawn on d4 and prepares to advance the e-pawn to e5. The knight on c6 also puts pressure on the white pawn chain and prepares Black's pieces for further development. Additionally, this move helps to prepare for a tactical maneuver of c5, which can help to undermine White's control of the center. In sum, the move Nc6 helps Black to counter White's aggressive play and sets up an opportunity for an attacking game.