Q. What is an open textbook?
Covering a wide range of disciplines, open textbooks are freely available, under an unrestricted license, to download and print in various file formats from several web sites and OER (open educational resources) repositories. Many organizations provide access to open textbooks through their websites. Several file formats are made available for open textbooks; typical formats are HTML, Adobe PDF, and plain text.
An open textbook is a body of educational content that is openly available over the web, by mail, or in a book store with copyright that allows copying and distribution or, with the most open copyrights, allows modification of the content and even sale.