Réti Opening: Anglo-Slav Variation, Bogoljubov Variation

In the Réti Opening: Anglo-Slav Variation, Bogoljubov Variation, the move 1.Nf3 serves as an excellent tool for White to exert early pressure on the center of the board. By developing the knight to f3, White not only prepares to castle kingside but also paves the way for the pawn advance to d4, which can be played in a single move or after the intermediate move c2-c4. Additionally, the knight on f3 controls the key squares e5 and d4, thereby limiting Black's pawn breaks and central counterplay. This flexible move order enables White to adjust the position based on Black's responses, keeping the initiative while avoiding premature commitments.

By playing 1...Nf6 in response to 1.Nf3, Black aims to control the central square e4 and prepare for the development of their own pieces. The knight on f6 also attacks the pawn on e4, which may prompt White to reinforce it with d2-d3 or trade pieces with 2.e4 dxe4 3.Ng5. Additionally, the move Nf6 opens up the possibility of playing e7-e5, which would challenge White's control of the center and create space for Black's light-squared bishop. This move order also allows Black to delay their decision on whether to play d5 or c5, maintaining flexibility and preventing White from securing a clear target.

Playing c2-c4 is a common move in the first few moves of many chess openings, and in the case of 1.Nf3 Nf6, it has several aims. By advancing the pawn to c4 on the second move, White gains control of the central square d5 and prepares to establish a strong pawn presence there with d2-d4. The pawn on c4 also supports White's pieces on the queenside, and may provide opportunities for attacking Black's position along the c-file or b-file. Additionally, playing c4 allows White to develop the light-squared bishop on b2, creating a diagonal aimed at Black's king and providing tactical possibilities in the center and on the queenside. Playing c2-c4 also prevents Black from occupying the center with a pawn on d5 and restricts the mobility of Black's knight on b8.

In the Réti Opening: Anglo-Slav Variation, Bogoljubov Variation, playing 2...c6 is a flexible move for Black that controls the central square d5 and prepares to support the pawn on d5 after White's expected pawn advance d2-d4. By playing c6, Black also restricts the scope of White's knight on c3, which can no longer occupy the desirable square d5 without first exchanging on c6. This move order can lead to Slav-like pawn structures, where Black's pawn on c6 supports their pawn on d5 and prevents White from gaining space in the center with a pawn on c4. Additionally, playing c6 often prepares for an eventual b7-b5 pawn push, gaining space on the queenside and creating a target for Black's queen bishop.

In the opening sequence of 1.Nf3 Nf6 2.c4 c6, playing 3.b3 is a flexible and strategic move for White. By developing the light-squared bishop to b2, White prepares to exert pressure on the long diagonal and potentially support a later pawn advance to d4, which may break open the center. B3 is also a useful move for maneuvering the knight on c3 to a more active square, such as d2 or e5, while avoiding exchanges with Black’s knight on f6. This move also prevents possible pins against the bishop on c1 by Black's knight on b4, and may prepare for an eventual pawn push to a4, gaining space on the queenside and potentially creating targets.

In the given opening sequence of 1.Nf3 Nf6 2.c4 c6 3.b3, playing d7-d5 is a logical move for Black, as it gains space in the center and contests White's control of the d4-square. By occupying the center with a pawn, Black gains a foothold for their minor pieces to develop and potentially counterattack White's position. Establishing a pawn on d5 also frees up the light-squared bishop, which now has access to the long diagonal and may exert pressure on White's kingside. Additionally, playing d5 can discourage White from playing d2-d4 immediately, as this would result in a pawn exchange and relieve Black's central pawn majority. By playing this move, Black challenges White's control of the center and aims to equalize the position.

In the Réti Opening: Anglo-Slav Variation, Bogoljubov Variation, playing Bb2 is a natural move for White that completes the development of the light-squared bishop and supports the pawn on c4. The bishop on b2 also exerts pressure along the long diagonal, potentially targeting Black's king or queen. By placing the bishop on this diagonal, White also creates a battery with their queen, which may have tactical possibilities against Black's kingside. Additionally, the bishop on b2 provides support for the pawn on d4 after the move d2-d4, which may lead to a central pawn structure with a pawn chain stretching from d4 to b2. This move also prepares for the potential relocation of the knight on c3 to the square d2, completing the knights’ maneuver and enabling the advance e2-e4.