The academic year is divided into two semesters: fall term and spring term. The former lasts approximately from the end of September until mid February. The latter lasts usually from mid-February to the end of June. Each semester has a) a lecture period in which students attends weekly lectures and b) an exam period (there are no more lectures; students prepare for their exams and work on their papers). The lecture period of the winter term is usually from the end of September until mid December. The lecture period of the summer term is usually from mid February until mid May.