Different religions may or may not contain various elements ranging from the divine, sacred things, faith, a supernatural being or supernatural beings or "some sort of ultimacy and transcendence that will provide norms and power for the rest of life". Religious practices may include rituals, sermons, commemoration or veneration (of deities), sacrifices, festivals, feasts, trances, initiations, funerary services, matrimonial services, meditation, prayer, music, art, dance, public service, or other aspects of human culture. Religions have sacred histories and narratives, which may be preserved in sacred scriptures, and symbols and holy places, that aim mostly to give a meaning to life. Religions may contain symbolic stories, which are sometimes said by followers to be true, that have the side purpose of explaining the origin of life, the universe, and other things. Traditionally, faith, in addition to reason, has been considered a source of religious beliefs.
There are an estimated 10,000 distinct religions worldwide, but about 84% of the world's population is affiliated with one of the five largest religions, namely Christianity, Islam, Hinduism, Buddhism or forms of folk religion. The religiously unaffiliated demographic includes those who do not identify with any particular religion, atheists and agnostics. While the religiously unaffiliated have grown globally, many of the religiously unaffiliated still have various religious beliefs.
The study of religion encompasses a wide variety of academic disciplines, including theology, comparative religion and social scientific studies. Theories of religion offer various explanations for the origins and workings of religion.
Religion (from O.Fr. religion religious community, from L. religionem (nom. religio) "respect for what is sacred, reverence for the gods", "obligation, the bond between man and the gods") is derived from the Latin religiō, the ultimate origins of which are obscure. One possible interpretation traced to Cicero, connects lego read, i.e. re (again) with lego in the sense of choose, go over again or consider carefully. The definition of religio by Cicero is cultum deorum, "the proper performance of rites in veneration of the gods." Modern scholars such as Tom Harpur and Joseph Campbell favor the derivation from ligare bind, connect, probably from a prefixed re-ligare, i.e. re (again) + ligare or to reconnect, which was made prominent by St. Augustine, following the interpretation given by Lactantius in Divinae institutiones, IV, 28. The medieval usage alternates with order in designating bonded communities like those of monastic orders: "we hear of the 'religion' of the Golden Fleece, of a knight 'of the religion of Avys'".
In the ancient and medieval world, the etymological Latin root religio was understood as an individual virtue of worship, never as doctrine, practice, or actual source of knowledge. Furthermore, religio referred to broad social obligations to family, neighbors, rulers, and even towards God. When religio came into English around the 1200s as religion, it took the meaning of "life bound by monastic vows". The compartmentalized concept of religion, where religious things were separated from worldly things, was not used before the 1500s. The concept of religion was first used in the 1500s to distinguish the domain of the church and the domain of civil authorities.