"Open textbooks are textbooks that have been funded, published, and licensed to be freely used, adapted, and distributed. These books have been reviewed by faculty from a variety of colleges and universities to assess their quality." Initiative of the Open Textbook Network.
"Open textbooks can be found in the B.C. Open Textbooks Collection, as well as, several other repositories and collections. Some open textbooks contain supplemental or ancillary materials (e.g., test banks, quizzes, PowerPoint slides, videos). Textbooks that include one or more ancillary resources in the B.C. Open Textbooks Collection are marked with an Ancillary Resources flag."