The course section overview report is constructed of data from the course section table as well as the student academic credit table. For each course section you can see the number of students who are/were registered, cumulative attempted credits, cumulative completed credits, and more.
When you first click on the link to the course section overview report under the reports menu, it will automatically default to the current year (based on course section start date). As mentioned previously, one of the columns on this report is the number of students. Drilling down on a particular course section will allow you to see the students and will bring you to the Student Academic Credit report.