"Outline displays" control how a learner views, enrolls and navigates through a course.
Course: Forces the learner to move through the course in a linear workflow.
None: Used for placeholder courses that cannot be enrolled in or taken.
Imported: Used for holding data needed for imported course completion records.
Relationships: Allows the learner to select from related courses. Used for curricula, conferences and other complex activity types. Courses with the "relationship" outline display cannot contain course objects. They can only be linked to other courses. Learn more about course relationships here.
External system: Usually used for representing an external course in the catalog. The learner is redirected to the URL entered into the "External URL" field when enrolling. It is recommended to disable "show on transcript" to keep the course from appearing on the transcript.