This document discusses open educational resources (OER) and the global OER movement. OER are teaching materials like textbooks, videos, and readings that are free to access and allow users to retain, reuse, revise, remix, and redistribute the materials. The global OER movement aims to make education more affordable and accessible by promoting the creation and use of OER under open copyright licenses. Research shows that using OER can significantly reduce costs for students and lead to equal or better learning outcomes compared to traditional textbooks.