Nocturne of Shadow
The Nocturne of Shadow is a teleporting song for the Ocarina in Ocarina of Time, and it is really easy to find where to learn it. It teleports you to the Triforce Pedestal outside of the Shadow Temple.
How to Learn it
To learn it, you must first have completed the Water Temple and the Fire Temple. All you have to do is go to Kakariko Village, where you will experience a cutscene involving a monster escaping the well, Sheik getting thrown into the air, and Link getting knocked out. This monster is actually the boss of the Shadow Temple, Bongo Bongo. Afterwards, Sheik will teach you the Nocturne of Shadow.
How to Play it
To play it on your Ocarina in Ocarina of Time, play the following notes using the C-Buttons: ← → → A ← → ↓.
In the 3D version, just play the following notes: X Y Y L X Y R.