Wondrium (formerly The Great Courses Plus and originally The Great Courses) is a US online education platform that has been publishing university-level video lecture series since 1990. The platform's distinctive contribution is the depth and production quality of its courses — each is taught by a tenured university professor with the production values of a documentary series, not a YouTube tutorial.
The catalog covers academic disciplines rather than technical-skill training: history, philosophy, science, mathematics, literature, music theory, religion, economics. Material is taught by faculty from Stanford, Yale, Princeton, the University of Chicago, MIT, and similar institutions. Wondrium is typically used by intellectually-curious adult learners filling in the liberal-arts side of their education.
The CourseFlix listing under this source carries over 19 Wondrium / Great Courses titles spanning that range — sitting in the broader CourseFlix catalog as general-interest reference rather than as a software-engineering track. Material is paid; Wondrium itself runs on a monthly / annual subscription on the original platform.