precede vs prolog

precede

noun
  • Brief editorial preface (usually to an article or essay) 

verb
  • To have higher rank than (someone or something else). 

  • To go before, go in front of. 

  • To cause to be preceded; to preface; to introduce. 

prolog

noun
  • A speech or section used as an introduction, especially to a play or novel. 

  • A component of a computer program that prepares the computer to execute a routine. 

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