Courses and categories allow you to organize your cases within your product. Each case requires one course and one category, but you can be as specific as you like up to three levels of categorization. For example, you might create a Musculoskeletal course, and under that create a level 1 category for Arm, a level 2 category for Hand, and a level 3 category for Finger. This level of categorization allows Cortex to provide more specific results when searching and filtering.