"Course Genre"

All professors are knowledgeable and informative. I have dozens of courses on a wide spectrum of topics. Only a few professors are slightly biased giving their own twist on the subject matter. That's OK as I usually catch them as I go through the lectures. The quality of the DVDs are excellent so far. Very few verifiable errors that I catch now and then. I recommend the Great Courses for continued learning as I've learned a lot from them. I find the courses in science and math very enlightening.