narrator vs orator

narrator

noun
  • The person providing the voice-over in a documentary. 

  • One who narrates or tells stories. 

  • The person or the "voice" whose viewpoint is used in telling a story. 

orator

noun
  • A skilled and eloquent public speaker. 

  • Someone who orates or delivers an oration. 

How often have the words narrator and orator occurred in a corpus of books? (source: Google Ngram Viewer )