Petrov's Defense: Modern Attack is a chess opening with the ECO code C43, part of the Petrov's Defense family. It goes 1. e4 e5 2. Nf3 Nf6 3. d4 exd4. White opens with 1. e4 (the king's pawn) and Black answers 1... e5. After 6 moves it is White to move. After the last move Black 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. e4 – White plays the pawn to e4
1... e5 – Black plays the pawn to e5
2. Nf3 – White plays the knight to f3
2... Nf6 – Black plays the knight to f6
3. d4 – White plays the pawn to d4
3... exd4 – Black captures on d4 with the e-pawn
About the Petrov's Defense
After 1.e4 e5 2.Nf3, Black counterattacks e4 with 2...Nf6 instead of defending e5. It is symmetrical and very solid.
After 3.Nxe5, do not copy with 3...Nxe4?; first play 3...d6, then take.
The trap: 3...Nxe4? 4.Qe2 and the pin on the e-file wins material.
Black aims for quick development and a safe, equal position.