Book - this is for referencing the overall book by an author(s)?
Book Chapter - this is a chapter (and specific page(s) within a book), such as when using a direct citation?
Edited Book - This is for a book that is collection of chapters by individual authors (usually experts in a specific field of knowledge), which is then complied into an book with an overall editor - An example from my field of research is "The Gower Handbook of Project Management" or the "Association for Project Management Pathways". Both have chapters written by recognised academics within their field of knowledge.
To clear this confusion up would be great as I build my dissertation and aid my learning process

Thanks,