1. e4 e5
2. Nf3 Nf6
the main line preaches you should continue
3. Nxe5 d6
4. Nf3 Nxe4
5. d4 d5
chess notation
This is a very active opening in chess which intially involves black copying whites moves. There are many reasons to play the Petroff. One is that it is a nice way to avoid the Ruy Lopez which is a lot of work to study. Another is to draw your opponent or to begin with an even opening. Here is the stupidest way people ever play the Petroff.
The stupidest thing black can do while playing Petroff
1. e4 e5
2. Nf3 Nf6
3. Nxe5 Nxe4
4. Qe2 Nf6 (Ok, here's the thing, please don't fucking do this.)
5. Nc6+
Whites queen checks black and whites knight will take blacks queen. A good idea when playing the Petroff is to not capture white's pawn right away but to drive the knight away first, maybe exchange queens(though being the one to initate the queen exchange will probably lose you tempo), and then collect the pawn a couple moves after.
The main point of the Petroff is to force draw games. If you play it a few times and mostly mimick your opponent you will see what I mean. Usefull for drawing beter players and eating up their ratings or if you love endgames this opening might appeal to you as you can force a quick endgame. An intresting continuation of the Petroff is the Cochrane Gambit, in which white sacrifices a knight for two pawns and an exposed black king
chess openings
Endgames in Chess | 
