built-in vs part and parcel

built-in

noun
  • Anything (such as a piece of furniture, or a software feature) that is built in, not added as an extra. 

adj
  • Being an essential and permanent part of something. 

  • Being an included feature that normally comes as an extra. 

  • Constructed as a non-detachable part of a larger structure. 

part and parcel

noun
  • An integral or essential piece; that which must be done or accepted as part of something else. 

How often have the words built-in and part and parcel occurred in a corpus of books? (source: Google Ngram Viewer )