Grade Categories can be used to organize your grade items into groups. Grade categories can also be used to drop high and/or low scores from a group of grade items.
Grade Items represent the work on which you wish to evaluate students in your course. Different types of grade items can be created depending on how you wish to evaluate the work. For example, grade items can be numerically graded or based on a grade scheme. Grade items can exist independently, or you can associate numeric grade items with activity tools such as Assignments, Discussions, and Quizzes. Each grade item has an entry in which you assign a grade for each student.
Grade items can exist within or outside of grade categories.