commentary vs criticism

commentary

noun
  • A series of comments or annotations; especially, a book of explanations or expositions on the whole or a part of some other work. 

  • An oral relation of an event, especially broadcast by television or radio, as it occurs. 

  • A brief account of transactions or events written hastily, as if for a memorandum. 

criticism

noun
  • The act of criticising; a critical judgment passed or expressed 

  • A critical observation or detailed examination and review. 

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