Nerves which start directly from the brainstem instead of the spinal cord.

In human anatomy, there are exactly 12 pairs of them, and they are named, in order:

  1. Olfactory nerve (I)
  2. Optic nerve (II)
  3. Oculomotor nerve (III)
  4. Trochlear nerve (IV)
  5. Trigeminal nerve (V)
  6. Abducens nerve (VI)
  7. Facial nerve (VII)
  8. Vestibulocochlear nerve (VIII), sometimes called the auditory nerve
  9. Glossopharyngeal nerve (IX)
  10. Vagus nerve (X)
  11. Accessory nerve (XI), sometimes called the spinal accessory nerve
  12. Hypoglossal nerve (XII)

Many mnemonics exist for this listing but perhaps the one best remembered is: Oh, Oh, Oh To Touch And Feel Virgin Girls Vaginas and Hymens.
