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 form of salvation. Studying such material is meant to give one a richer 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 includes Middle Eastern religions (including Zoroastrism and Iranian religions), Indian religions, East Asian religions, African religions, American religions, Oceanic religions, and classical Hellenistic religions.
According to Charles Joseph Adams, in the field of comparative religion, a common geographical classification discerns the main world religions as follows:
In the study of comparative religion, the category of Abrahamic religions consists of the three monotheistic religions, Christianity, Islam and Judaism, which claim Abraham (Hebrew Avraham אַבְרָהָם ; Arabic Ibrahim إبراهيم ) as a part of their sacred history. Other religions (such as the Bahá'í Faith) that fit this description are sometimes included but are often omitted.