début vs intro

début

verb
  • To make one's début. 

noun
  • A person’s or thing’s first appearance before society or another audience; one’s “maiden voyage”. 

intro

verb
  • To introduce. 

noun
  • The opening sequence at beginning of a film, television program, etc. 

  • An introduction. 

  • A small demo produced to promote one's demogroup or for a competition. 

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