interpreter vs travel book

interpreter

noun
  • A guide who helps people visiting an attraction such as an art exhibit, a nature reserve, etc., understand what they are seeing. 

  • A program that executes another program written in a high-level language by reading the instructions in real time rather than by compiling it in advance. 

  • A person who converts spoken or signed language into a different language for the benefit of one or more others who do not understand the first language being used (especially if in real time or shortly after that person has finished communicating). (Contrasted with translator.) 

  • Something that reveals or clarifies. 

  • A person who interprets. 

travel book

noun
  • A book about travelling to a certain region, such as a memoir or guide book. 

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