A massive open online course (MOOC) is an online course with unlimited participation and open access on the web. MOOCs provide video lectures, readings, problem sets and interactive user forums to help build a community for students, professors and teaching assistants. They are a recent development in distance education that emerged in 2012. While early MOOCs emphasized open licensing of content to promote reuse, some newer MOOCs use closed licenses for materials while maintaining free access for students.