Philidor Defence: free opening course

Key ideas

• Support e5 with the d6 pawn and develop calmly. The knight goes to f6, the bishop to e7, and you castle short.
• Against 3.d4 the simple way is 3...exd4. You give up the centre but get easy development.
• Keep an eye on f7. A white bishop on c4 and a knight on g5 often aim at it together.
• Do not pin the f3 knight with ...Bg4 too early. White can often ignore the pin and win material.
• If White takes on e5 and offers a queen trade, do not take back with the d-pawn. The e5 pawn would be lost.

The 6 variations in the course

• 3.d4 exd4 4.Nxd4: the Exchange Variation: 1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 Be7 6. Bf4 O-O … — Black takes on d4 and develops with ...Nf6, ...Be7 and short castling. White often castles long and attacks. Black trades a pair of knights and gains space on the queenside with ...a6 and ...b5.
• 3.d4 exd4 4.Qxd4: the queen takes back: 1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Qxd4 Nc6 5. Bb5 Bd7 6. Bxc6 Bxc6 … — White takes back with the queen. Black gains time by attacking it with ...Nc6. After the trade on c6 Black gets the two bishops, castles short and has a solid game.
• 3...Nf6 4.Nc3 Nbd7: the Lion set-up: 1. e4 e5 2. Nf3 d6 3. d4 Nf6 4. Nc3 Nbd7 5. Bc4 Be7 6. O-O O-O … — Black keeps the pawn on e5 and plays ...Nbd7, ...Be7, short castling and ...c6. Black's position is a little cramped but very solid. Later Black frees the game with ...exd4 and ...d5.
• 3...Nf6 4.dxe5 Nxe4: the early capture: 1. e4 e5 2. Nf3 d6 3. d4 Nf6 4. dxe5 Nxe4 5. exd6 Bxd6 6. Bd3 Nc5 … — White takes on e5 at once. Black must take back on e4 with the knight, not on e5 with the pawn. After 5.exd6 Bxd6 Black develops fast and the game is equal.
• 3...Nd7: the Hanham Variation: 1. e4 e5 2. Nf3 d6 3. d4 Nd7 4. Bc4 c6 5. O-O exd4 6. Nxd4 Ngf6 … — Black supports e5 with the knight. Against 4.Bc4 the careful move is 4...c6, because f7 is weak. Black then takes on d4 and develops the kingside.
• 3.Bc4 Be7: the calm answer: 1. e4 e5 2. Nf3 d6 3. Bc4 Be7 4. d4 exd4 5. Nxd4 Nf6 6. Nc3 O-O … — White's most common third move puts the bishop on c4. Black answers calmly with 3...Be7. After d4 and the trades in the centre, Black uses the fork trick. The moves ...Nxe4 and ...d5 free the game.

Traps you will learn (3)

• Légal's Mate: 6...Bxd1?? — Black pins the f3 knight with ...Bg4 and keeps it on h5. White takes on e5 anyway and offers the queen. If Black takes the queen, Bxf7+ and Nd5 give checkmate with three minor pieces.
• 4.Ng5 Be6? 5.Nxe6: f7 is still weak — After 3.Bc4 Nf6 4.Ng5 the knight and bishop both hit f7. Covering with 4...Be6 looks natural, but White takes on e6 and wins a pawn. Black's king stays weak.
• 4.dxe5 dxe5? 5.Qxd8+: the queen trade — After 3...Nf6 4.dxe5 many players take back with the d-pawn. White trades queens with check and the knight takes the e5 pawn. Black loses a pawn and cannot castle.

How the opening courses work

Each course teaches an opening in a few main variations. For every move you read why it is played, which other moves are good, and which tempting moves are mistakes and why. Each course also shows the traps of the opening: the ones you can set and the ones to avoid.

After a lesson you play the moves yourself in a drill. The lines you learn go into your review, which brings them back when you are about to forget them (spaced repetition). 30 line courses add many short lines per opening, a few new ones a day, and every named opening, more than 3,800 lines, has a lesson of its own.