Open Educational Resources were created by professors and course instructors to help reduce the cost of education. Texts and materials were developed under a Creative Commons license so they can be freely used by all.
Need more? Search online for "open textbooks" or "open educational resources"
Click to find lists of physics textbooks. The emphasis is on 1st and 2nd year texts as the initial focus for open resources is on popular courses. Explore the sites to find the information you need. Some collections include materials such as lecture notes, assignments, sample tests, labs, etc.
eCampus Ontario
LibreTexts - core modules in astronomy and cosmology
OER Commons
OpenStax - science textbooks, solutions, resources
Open Textbook Library - physics textbooks
MIT Open Courseware
Open Yale Courses