What is a course pre-requisite? What is a course co-requisite?

A pre-requisite is a course that must be taken before the course in question is started.

A co-requisite is a course that should be taken concurrently with or before the course in question.

The Department of Earth System Science (ESS) actively checks pre-requisites and co-requisites. Before registering for classes, check the current Course Catalogue to see if there are any pre-requisites or co-requisites for the courses in which you plan to enroll. In most cases, the pre- and co-requisites are also listed online in the schedule of classes.

In some instances, a pre- or co-requisite can be waived by consent of instructor.