There are an estimated 4,200 different religions in the world, and these can be categorized into several main religions. These include Christianity, Roman Catholicism, Islam, Hinduism, Buddhism and Judaism, although Roman Catholicism is often categorized under Christianity. There are many smaller yet still prevalent religions, such as the Baha'i faith.
When including Roman Catholicism, Christianity is the world's largest religion. Christianity also includes Protestantism and its many denominations, such as Lutherans, United Methodists, Southern Baptists and the Assemblies of God. There are also nondenominational Christians.
Islam is prevalent in the Middle East and Southeast Asia, and is broken into the Sunni, Shia and Sufi groups. Hinduism is dominant in India. Buddhism is prevalent in Asia, such as Cambodia, Laos and Thailand, although it originated in India. One variant of Buddhism is Zen Buddhism. Judaism originated in Israel, and Baha'i in Iran. There are also numerous indigenous or folk religions throughout the world.