Comparative religion is the branch of the study of religions concerned with the systematic comparison of the doctrines and practices of the world's religions. In general the comparative study of religion yields a deeper understanding of the fundamental philosophical concerns of religion such as ethics, metaphysics, and the nature and forms of salvation. Studying such material facilitates a broadened and more sophisticated understanding of human beliefs and practices regarding the sacred, numinous, spiritual, and divine.In the field of comparative religion, a common geographical classification of the main world religions distinguishes groups such as Middle Eastern religions (including Iranian religions), Indian religions, East Asian religions, African religions, American religions, Oceanic religions, and classical Hellenistic religions.