Google Books offers free previews of many different free and premium books. Many of these books may be purchased through Google Play, and some may also be free to read, such as classic books that are no longer under copyright protection.
Books.Google.com divides available books into a variety of genres. Clicking on a book shows details about that book, such as the author, publisher, description and reviews. Clicking on the cover for a book opens a new preview. This view is scrollable and displays content from inside the book. The amount of content that's available varies from book to book and is dependent on whether the book is being sold or is free to download or read on Google Play.