Many courses offered by the university are open to any interested student, space permitting. However, some courses havepre-requisites - other courses or test scores a student must have had before taking the course in question, in order to understand it. For other courses, there are recommendations regarding courses or experiences that might be beneficial, but not necessary, to have. A few courses haveco-requisites, which must either be taken before or together with the course in question. Information about pre-and co-requisites, and other recommended experiences, is given in the course description section found elsewhere in this catalog. Students are responsible for ensuring that any pre-requisites have been met before enrolling in a course.