King's Indian Attack, with Bf5 is a chess opening with the ECO code A07. It goes 1. Nf3 Nf6 2. g3 d5 3. Bg2 c6 4. O-O Bf5 5. d3 e6 6. Nbd2. White opens with 1. Nf3 (the Zukertort/Réti knight move) and Black answers 1... Nf6. After 11 moves it is Black to move. The lesson on the board explains every move of the line and lets you play it yourself; it is free.
The moves
1. Nf3 – White plays the knight to f3
1... Nf6 – Black plays the knight to f6
2. g3 – White plays the pawn to g3
2... d5 – Black plays the pawn to d5
3. Bg2 – White plays the bishop to g2
3... c6 – Black plays the pawn to c6
4. O-O – White castles kingside
4... Bf5 – Black plays the bishop to f5
5. d3 – White plays the pawn to d3
5... e6 – Black plays the pawn to e6
6. Nbd2 – White plays the knight to d2
About the King's Indian Attack, with Bf5
White sets up Nf3, g3, Bg2, O-O, d3 and later e4: a King's Indian with colours reversed. It is an easy system against almost anything.
White plays Nbd2, e4 and often e5 to gain kingside space.
With a pawn on e5, White attacks with Nf1, h4 and Ng5 or Nh2-g4.
Black usually expands on the queenside with ...c5, ...b5 and ...b4.