The IB Diploma Programme is a two-year comprehensive curriculum with a culminating set of externally graded final exams. IB, Advanced Placement (AP) and other college-preparatory curriculums like Cambridge are all university preparatory, academically rigorous programmes. There are important differences, however, in the content and exams. The DP is a cohesive and comprehensive programme, not a collection of individual courses as is the case with Advanced Placement. The most important distinguishing factor is the core of the Diploma Programme (CAS, TOK and extended essay).