Courses are often offered more than once. In Blackboard Learn, you can merge courses and manage multiple sections and crosslisted courses from one central location.
Instructors sometime teach multiple sections of the same course. System administrators can merge the rosters of those courses into one master course. Merging the rosters allows the instructors teaching multiple sections of the same course to manage the content, course management, and communications tasks for all sections of the course from one central location.
Institutions commonly offer a course under multiple programs. For example, an advanced literature course might be available for credit in an English degree program as well as a Journalism program. Instructors and registrars are challenged with managing student enrollment, grading, and content being used in a single course. Crosslisting is the act of delivering two or more courses/sections as a single combined course. In physical world terms, students with different courses listed on their timetables would show up in the same classroom and get taught at the same time. In Learn terms, students would see a course they are enrolled in on their My Courses tabs, but when clicking to enter it, will share the same course content as all other students across all combined courses.