Open textbook is a textbook licensed under an open copyright license and made available online to be freely used by students, teachers, and members of the public.

• They are available for free as online versions and in a variety of file formats (e.g., for eReaders, editable files like XML and HTML), and as low-cost printed versions, should students or faculty opt for these.
• Open textbooks are a way to significantly reduce student textbook costs while giving instructors the flexibility to reformat and customize their course material.
• They are an affordable, flexible alternative to traditionally published textbooks.