Open Library is an initiative of the Internet Archive, a 501(c)(3) non-profit, building a digital library of Internet sites and other cultural artifacts in digital form.

Open textbooks are licensed by authors and publishers to be freely used and adapted. Download, edit and distribute them at no cost.

Project Gutenberg is a library of over 60,000 free eBooks. Choose among free epub and Kindle eBooks, download them or read them online.

DOAB is a discovery service for peer reviewed open access books and book publishers that indexes and provides access to high quality, open access, peer-reviewed books.