folio vs playbook

folio

noun
  • a leaf of a book or manuscript 

  • A page in an account book; sometimes, two opposite pages bearing the same serial number. 

  • A book made of sheets of paper each folded in half (two leaves or four pages to the sheet); hence, a book of the largest kind, exceeding 30 cm in height. 

  • A page number. The even folios are on the left-hand pages and the odd folios on the right-hand pages. 

  • A wrapper for loose papers. 

  • A page of a book, that is, one side of a leaf of a book. 

  • A sheet of paper folded in half. 

verb
  • to put a serial number on each folio or page of (a book); to page 

playbook

noun
  • A book containing the text of a play or plays. 

  • A set of commonly employed tactics and strategies. 

  • A book of games and amusements for children. 

  • A book of strategies (plays) for use in American football (and by extension other sports or disciplines). 

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