Philidor Defense: Hanham Variation, Krause Variation

The Philidor Defense is a solid and careful way to meet White's first move with 1...e5. After 2.Nf3, Black continues with 2...d6, aiming to control the center with his pawns. White's move 3.d4 strikes at the center and opens lines for his pieces. After 3...Nd7, White plays 4.Bc4 with the idea of preparing to castle kingside and attacking the black pawn on f7. The move 5.O-O completes White's development and brings his king to safety. In sum, this opening is a good choice for Black players who prefer a solid and less tactical approach to the game.

When Black plays 1...e5 in response to 1.e4, he aims to control the center and contest White's initiative from the very beginning of the game. The pawn on e5 gives Black a strong hold on the d4 square, limiting the scope of White's pieces and paving the way for the development of Black's own forces. This move also enables the pawn on f7 to support the knight on g8, which prepares to enter the game via f6 or d6. In sum, 1...e5 is a classical and aggressive response to White's opening move that has stood the test of time.

White's move 2.Nf3 develops the knight towards the center and supports the pawn on e4. It also puts pressure on Black's pawn on e5, threatening to capture it if black doesn't take preventive measures. This move prepares the way for the development of other pieces, such as the kingside bishop and the castle kingside on the next move. Furthermore, by having a piece developed, White can exert more control over the board and be better prepared for whatever Black's response may be. In sum, 2.Nf3 is an important step in the opening game that has been employed by many top-level players.

In the Philidor Defense: Hanham Variation, Krause Variation, Black typically responds to 2.Nf3 with 2...d6. This move aims to support the pawn on e5, preventing its capture by White's knight and keeping control of the center. Additionally, 2...d6 allows the Black's light-squared bishop to be developed diagonally towards f5. Another idea behind this move is to prepare to castle and secure the king's safety. In sum, 2...d6 is a solid and flexible move that can lead to different variations depending on White's response.

White's move 3.d4 strikes at the center and challenges Black's pawn on e5, aiming to open the position and create opportunities for his pieces. If Black takes the pawn with 3...exd4, White recaptures with the queen, unpinning her and putting pressure on the knight that defends the pawn on e5. If Black plays 3...Nd7, White can continue with 4.Nc3 or 4.Bc4, both aiming to complete his development and put pressure on Black's position. Furthermore, by establishing a pawn on d4, White can gain more space and limit the mobility of Black's pieces. In sum, 3.d4 is a dynamic and active move that can lead to highly tactical and challenging positions.

In response to 3.d4, Black often plays 3...Nd7. This move aims to protect the pawn on e5, which would be threatened if White were to capture the pawn on d6. Moreover, the knight on d7 may later be repositioned to f6, where it can protect the king and control important central squares. Additionally, 3...Nd7 prepares the way for the development of Black's queenside knight and bishop. In sum, 3...Nd7 is a solid and flexible move that delays Black's central pawn break but also allows him to further develop his pieces.

In the Philidor Defense: Hanham Variation, Krause Variation, White often plays 4.Bc4 after Black's move 3...Nd7. This move aims to develop the bishop and put pressure on Black's pawn on f7. Moreover, by placing the bishop on the long diagonal, White can potentially target the weak square h7 and create threats against the Black king. Another idea behind this move is to prepare to castle kingside, bringing the king to safety while also connecting the rooks. In sum, 4.Bc4 is a natural and aggressive move that can lead to sharp positions and requires careful handling from both sides.

In response to 4.Bc4, Black often plays 4...c6. This move aims to support the pawn on d5, restraining White's pawn on d4 and controlling the center. Moreover, 4...c6 prepares to develop the queenside knight to c7 followed by b5, potentially creating counterplay on the queenside. Additionally, the move 4...c6 can also discourage White's bishop from pinning the knight on f6 or attacking the pawn on f7. In sum, 4...c6 is a flexible move that allows Black to develop his pieces and claim more space on the board.

In response to 4...c6, White often castles kingside with 5.O-O. This move brings the king to safety and connects the rooks, while also putting additional pressure on the pawn on f7. Moreover, by castling, White can prepare to bring his rooks to the central files and potentially launch an attack against Black's position. Additionally, castling short is often the preferred choice in chess as it leads to a more solid and stable king's position, reducing the chance of a successful attack from the opponent. In sum, 5.O-O is a natural and strategic move that aims to complete White's development while also preparing for future plans.