The academic year starts on September 1st of each year and ends on August 31st of the following year. It is divided in two semesters (winter and spring), each of which comprises 13 weeks of teaching and two or three weeks of exams. By the end of every semester an exam period follows, while re-sit exams are held for either semester in September. The exact dates of each semester and the corresponding exam periods are determined by the University Senate.