An open textbook is an openly-licensed textbook offered online by its author(s). The open license sets open textbooks apart from traditional textbooks by allowing users to read online, download, or print the book at no additional cost.
For a textbook to be considered open, it must be licensed in a way that grants a baseline set of rights to users that are less restrictive than its standard copyright. A license or list of permissions must be clearly stated by the author.
Generally, the minimum baseline rights allow users at least the following:
The repositories below host numerous open textbooks:
Individual Books
The Mason OER Metafinder (below) searches across 18 different sources of open educational materials.
Openly Available Sources Integrated Search (OASIS) is a search tool that aims to make the discovery of open content easier. OASIS currently searches open content from 88 different sources and contains 352,755 records.