Open textbooks are free, online learning materials with Creative Commons licenses. Many of the collections will have links to the same books, but each will have a particular focus, and items you can't find in other collections.
OER repositories contain more than just open textbooks. All content featured within these pages is free but usage rights vary. Materials in these repositories are released under a Creative Commons license while some are in the public domain.
Search many repositories listed on this guide at the same time via the Mason MetaFinder. Can be overwhelming, so use precise search terms and eliminate repositories that contain irrelevant materials from the initial search.
Modified and adapted by the PALNI Affordable Education Initiative Taskforce.