Groups versus cohorts
Both groups and cohorts are collections of students. However, there are several differences between them. We can sum up these differences in one sentence, that is, cohorts are site-wide or course category-wide groups. Cohorts enable administrators to enroll and unenroll students en masse, whereas groups enable teachers to manage students during a class. So, you can think of a cohort as a collection of students who are staying together in order to complete an entire course or sequence of courses together. Groups are smaller sets of students within the course.
Here's another way to approach it: Think of a cohort as a group of students working together through the same academic curriculum; for example, a group of students all enrolled in the same degree program, and then they tend to have many courses together. For example, you may have a cohort (collection of students) who decide to pursue a Master's of Liberal Studies together. They will all be enrolled...