Overall-type questions are course-based questions pertaining to the course.  People based-type questions are faculty-based questions pertaining to each of the instructors.  The two are separated to allow for the evaluation of multiple instructors on a course.  Students will only answer Overall questions once on a survey, but if there are multiple instructors on a course, the system will assign the instructor-based questions to each individual instructor.  This will play a major role in reports data access as well.