executor vs handler

executor

noun
  • Someone appointed by a testator to administer a will; an administrator. 

  • A person who carries out some task. 

  • A component of a system that executes or runs something. 

handler

noun
  • An advisor or manager to a person occupying a position or office to which the speaker believes the holder does not possess the typical qualifications and/or experience. 

  • One who handles something (especially manually) or someone. 

  • A subroutine that handles a particular situation such as an event or exception. 

  • A controller, trainer, someone who handles a specified thing, animal or person (especially a prizefighter). 

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