King's Indian Defense: Orthodox Variation is a chess opening with the ECO code E91, part of the King's Indian Defense family. It goes 1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 O-O 6. Be2. White opens with 1. d4 (the queen's pawn) 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. d4 – White plays the pawn to d4
1... Nf6 – Black plays the knight to f6
2. c4 – White plays the pawn to c4
2... g6 – Black plays the pawn to g6
3. Nc3 – White plays the knight to c3
3... Bg7 – Black plays the bishop to g7
4. e4 – White plays the pawn to e4
4... d6 – Black plays the pawn to d6
5. Nf3 – White plays the knight to f3
5... O-O – Black castles kingside
6. Be2 – White plays the bishop to e2
In chessGM's opening book this position continues with 6... e5.
About the King's Indian Defense
Black plays ...Nf6, ...g6, ...Bg7, ...O-O and ...d6, letting White build a big centre, then strikes back at it. It is a fighting, attacking defence.
Black strikes the centre with ...e5 or ...c5.
When the centre locks with d5, Black attacks the king with ...f5, ...f4 and ...g5.
White usually attacks on the queenside with c5 and b4; it becomes a race.
chessGM