Courses are learning management components that define which piece of learning content (an assignment, a course module or course, a virtual lab or series of labs, and so on) is assigned to which users. And under which conditions this assignee (or assignees) have to pass the objective: the due dates, progress control, and so on.
The Courses menu contains learning content components (courses, course modules, and so on) that the course author has created.
As an online course instructor, you can manage an course as follows: