The Scotch Gambit is a chess opening beginning with the moves:

1. e4   e5

2. Nf3  Nc6

3. d4   exd4

4. Bc4 (see diagram)

as opposed to the Scotch Game
starting with the moves:

1. e4   e5

2. Nf3  Nc6

3. d4   exd4

4. Nxd4

The Scotch Gambit is an opening with a large potential for White. If Black doesn't know the line well, White has threats, tactics and much more!