The book is a collection of paper with the words that rolled into one. Reads the papers have the same theme of discussion and arranged according to specific chronology, from the initial discussion until its conclusion and the discussion. The book is a window of science. Specific knowledge used as a single entity within the book. So that knowledge is not dispersed and easy to learn, then the book was created. The purpose of the book is nothing but to unify certain knowledge that collects in one place so easily found and studied.
No book type variety, not just a book of science, such as story books, comic books, novels, and so on. Usually the books have a certain size that distinguishes it from other lettered paper unification. Generally, the book has a size that makes it easier to grip or carried by a person. Not too small and not too big, not too thick and not too thin. Practicality become another main objective of the book.