Benko Gambit is a chess opening with the ECO code A59. It goes 1. d4 Nf6 2. c4 c5 3. d5 b5 4. cxb5 a6 5. bxa6 g6 6. Nc3 Bxa6 7. e4 Bxf1 8. Kxf1 d6 9. g3. White opens with 1. d4 (the queen's pawn) and Black answers 1... Nf6. After 17 moves it is Black to move. After the last move White is a pawn ahead in material. 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... c5 – Black plays the pawn to c5
3. d5 – White plays the pawn to d5
3... b5 – Black plays the pawn to b5
4. cxb5 – White captures on b5 with the c-pawn
4... a6 – Black plays the pawn to a6
5. bxa6 – White captures on a6 with the b-pawn
5... g6 – Black plays the pawn to g6
6. Nc3 – White plays the knight to c3
6... Bxa6 – Black takes on a6 with the bishop
The line goes on for 5 more moves; the lesson shows them all.
In chessGM's opening book this position continues with 9... Bg7.
About the Benko Gambit
After 1.d4 Nf6 2.c4 c5 3.d5, Black offers a pawn with 3...b5. Black gets open queenside files and long-term pressure.
After cxb5 a6, Black opens the a- and b-files for the rooks.
Black fianchettoes with ...g6 and ...Bg7 to hit the queenside.
Black's queen often goes to a5 or b6, and the knights to b6 or a4.