Three knights opening. Doesn't really put any pressure on Black, but doesn't hurt White's game, neither. I used to play this quite a lot. Can transpose into Giuoco Piano, Scotch Game or Gambit, Goring Gambit, or - a long tine favourite of mine - the Belgrade Gambit.

Good development.

Rather conservative, but solid enough. 4.Bc4 would have transposed into a Giuoco Pianissimo - the 'Quietest' Game.

As White didn't trouble to place a bishop on b4 or c4, this pawn move is redundant. White could play 6.d3 here, just to drive that point home. It would also have freed the Q-side bishop to move.

Premature.

As the knight is unprotected, this light horse attack achieves only the loss of the knight. Better would have been 7.d3, attacking the e4-knight. If Black played 7...Nf6 in response, then 8.Bg5 would have threatened to scramble Black's K-side by exchanging (NxB) on f6. Black would have had to consider 8...Be7, whereat White could exchange advantageously by 9.Nxe7 Qxe7 and then consider, say, 10.Re1.

Again, a bargain that only profits Black. It is not merely the loss of material (two knights for two pawns (you really want six pawns for two knights)), but they represent(ed) your most active pieces right now. In effect White will have to begin the game all over again, whilst conceding a considerable head start in material, time and space.

In the circumstances, not a bad decision. Normally one wouldn't play this. Though in my early days I used to steer for this sort of thing, it is usually a losing proposition, unless you have - as Black has here - already a big advantage.