Course Partitions visually break up the various sections for the course for your learners and are a great way to modulize your course.
It's super simple - just go to the course in question, click the Course Content tab, Add Course Content and then click Course Partition.
Next, you'll be able to name the partition and add an optional description.
Lastly, simply click on the icon shown below and drag the partition to wherever you want it to be.