Schools of Buddhism refers to the various institutional and doctrinal divisions of Buddhism that have existed from ancient times up to the present. The classification and nature of various doctrinal, philosophical or cultural facets or schools of Buddhism is vague and has been interpreted in many different ways, often due to the sheer number (perhaps thousands) of different sects, subsects, movements, etc. that have made up or currently make up the whole of Buddhist traditions. The sectarian and conceptual divisions of Buddhist thought are part of the modern framework of Buddhist studies, as well as comparative religion in Asia.