The main objective of the program Google Book Search is to help discover books, not to read them from beginning to end. It's like we're in a bookstore and consult you the titles.
Search Where?
Books of the Google Book Search come from two sources :
• Partner Program Google Books : is an online program that allows publishers of all sizes include the contents of his books in main search results on Google. The publishers send their books, they are scanned digitally and add their content to search results, all for free. Can preview a few pages of these books, as if hojearíamos books in any library or bookstore. Also shown are links to booksellers and libraries to buy or borrow books.
• The Google Library Project has been associated with prestigious libraries around the world to include their collections in Book Search.
How do you look?
Find books on Google Book Search is very simple: just enter the keyword or phrase you want to search in the search box. For example, if we look for "history of madness" or a phrase, find all books that match your search terms.
Through Google Book Search can find virtually any type of book: fiction, nonfiction, reference, literature, textbooks, children's books, scientific books, medical, professional, educational and many more.
What other information presented with the search results? What are information available on the screen?

A- Al Clicking the title of the book we see a relevant page of this as well as information about the publisher. However, Google Books is still a Beta product, therefore, may not find a particular book, for this reason it is advisable to seek the information they want (instead of the title of a book) and if there are other books on the same subject.
B- About the book: author, year of publication, number of pages.
C- information is expanded on the book. Generally includes a review of it.
D- offers the possibility of creating our own library where we can catalog, reread, revise, and perform full-text search a customized selection of books.
E- This option allows us to determine what kind of display of the books we want to provide us with our search. Due to copyright laws, some books may have a full view, limited or no sight. We can display only a limited part (in some cases only a few sentences) of books that are protected by the copyright. If the book has no restrictions imposed by copyright and are considered public domain, we will consult fully (now you can search the text complete approximately seven million books).
F-Link that allows us to change the display of the results to display list of books or the covers of the same.