How do online universities work?
There are several online universities, and the "campus" is wherever your computer is located. Accreditation of the school is a must, and a flexible schedule enables the student to work & study at their own pace. These programs are primarily designed for adults, not those who have just graduated from high school. Taking a course or 2 online to supplement your class schedule is a horse of a different color. Just be sure your brick n mortar school will accept the credits if you're planning to add them to your transcript. However, if it's only to increase your knowledge in a particular subject - go for it!