@Jimmi08 It just appeared, but still has best descripted names (imo). (overhaul of Content and pages in new form).
Basically (as i always interpret) Literally a book construction)
Book is more to be seen as placeholder(=bundle), It has the overall title (as a book has).
Now the book has overall belonging content, divided in Chapters and Pages(real content).
Example : (suppose i am writer)
My book is called Journeys
In this Book i have each country i visited as a Chapter.
(eg India, Japan, US etc...)
Now inside each Chapter i create my Pages (content description/stories)
eg what did i do in India..> Pages content for (C) India, Pages for (C)Japan etc..
Where each piece could also/should contain(> notes: small description of what it is about).
Of course you have no real introduction (could be a chapter too) and no index (could be listing of all pages) and evt. sources (again maybe a chapter...
All these together are a Book. B)Title Ch) by asc nr's (index or list as 1 ?) Country on Alphabet? Pages ID's asc for corresponding chapter they belong to (imagination is the key).