HarvardX is the online education arm of Harvard University, distributing Harvard course content through the edX platform and other channels. HarvardX has produced some of the most widely-taken online courses ever, including CS50 (introduction to computer science) and a long list of liberal-arts and quantitative tracks.
The CourseFlix listing carries a HarvardX course. Material is paid; HarvardX courses are typically delivered as video lectures with structured problem sets, taught by Harvard faculty.
