A "Zero Cost course materials" course or ZCCM, is a course that does not require the student to purchase any type of course materials to fulfill the course. This can include a combination of any of the types of course materials listed below or have no course materials required.
Open Educational Resources that are free for students
Digital library resources that are free (and readily available) for students
Ex. Limited access to ebooks (1 user at a time, etc.) does not count to make a course a zero-cost course since access to the ebook is not guaranteed as readily available.
Public domain resources that are free for students
Faculty-created materials that are free for students (whether they are OER or not)
OR, no course materials are required for the course