This is not a resource for free full-text books. Google books contains mostly books that have existing copyright licenses. Links from a book title may include a scanned preview page or snippet with links to online bookstores for purchase, or libraries for borrowing. Useful for previewing a book before purchasing.
The NAP publishes more than 200 books a year on a wide range of topics in science, engineering, and medicine, providing authoritative information on important matters in science and health policy.
Project Gutenberg is a library of over 60,000 free eBooks. Choose among free epub and Kindle eBooks, download them or read them online. You will find the world's great literature here, with focus on older works for which U.S. copyright has expired. Thousands of volunteers digitized and diligently proofread the eBooks, for enjoyment and education.