What is the Book resource in Moodle?

Book Module makes it easy to create multi-page resources in a book-like format.

Websites can be imported directly into the book module. Book can be printed entirely or by chapter. Book allows you to have main chapters and sub-chapters, but it goes no deeper. In other words, sub chapters cannot have their own sub chapters, as the module is  intended to be a simple resource for teachers and students.

The book module is not interactive. Although Flash movies and other multimedia can be included in it.