This variable gives the principal religions of the country under consideration. The world's various religions can be conveniently placed in ten basic categories. The number appearing in parentheses indicates the percentage of the population which practises this religion.

(1) JUDAISM. Along with Christianity and Islam, Judaism is one of the three great monotheistic religions of the world. Judaism comprises two main sects: (1) Karaites and (2) Samaritans. This latter group includes the Mandaeans, who practise a syncretic faith drawing on Judaism and Christianity. It is practised mainly in Iran and Irak. The Mandaeans are followers of Saint John the Baptist.

(2) CHRISTIANITY. Christians belong to one of four groups: Catholics, Protestants, Anglicans, and Orthodox. Catholicism includes, in particular, Roman Catholics (the Vatican), Jansenism (Jansenist Church of Utrecht, in the Netherlands), Uniates, Copts (Egypt), Maronites (Lebanon), Chaldeans (Iran and Irak), Malabars (South India), Nestorians or Assyrians (Eastern Syria), and the Jacobite Church (Western Syria). Protestantism includes, in particular, Lutherans (Reformists), Calvinists (Presbyterians), Mennonites, Baptists, Methodists, Pentecostals, Quakers, Adventists, Mormons, Jehovah's Witnesses, and the Salvation Army.

(3) MUSLIM (ISLAM). Most Muslims belong to one of two groups: (1) Sunni or Sunnite, and (2) Shiia or Shiite. Religions which have sprung from Islam include the Ismailis, Ahmadis, Yazidis, and Druzes (the latter faith drawing on Islam, Judaism, and Christianity). Except where otherwise indicated (and except for the Druzes), these categories are labeled MUSLIM in the data tables.

Among those religions which have sprung from Islam, one may include the Baha'i Faith. Baha'i believe in the unity of all religions and teaches "universal faith". The Baha'i Faith grew from Babism, a religious movement within Shiite Islam, founded in the 19th century in Persia by Mirza Ali Muhammad of Shiraz, who proclaimed himself the Bab in 1844. A disciple of the latter, Bab Mirza Husayn Ali, known as "Baha Ullah" (1817-1892), spread the Faith's influence worldwide. Other religions which have emerged from Islam include that of the Parsis, which combines characteristics of Mazdaism and Islam, and which is mostly found in Iran and India. The Parsis are followers of Zoroaster.

(4) HINDUISM. Religions which have sprung from Hinduism include those of the Jains and the Sikhs. The Sikh religion is a syncretic faith drawing on Hinduism and Islam. Their main site of worship is the Golden Temple in Amritsar (India).

(5) BUDDHISM. Buddhism embraces two main currents of thought: Mahayana (Greater Vehicule) and Hinayana (Lesser Vehicule).

(6) CHINA. The two main religions of China are Confucianism and Taoism. Buddhism was also introduced in China more recently. Confucianism and Taoism are not religions in the strict sense, but rather philosophies.

(7) SHINTOISM. Shintoism is practised mainly in Japan, and preceded Buddhism there.

(8) ANIMISM. Those religions which are commonly known as "animistic" include Shamanism, Druidism, Paganism, Pantheism, Polytheism, Spiritism, Fetishism, and Folklorism.

(9) SYNCRETISM. Syncretic faiths are characterized by a blend of religious influences. Such faiths include Voodoo (animism and Catholicism), Umbanda (animism and Catholicism), the Sikhs (Hinduism and Islam), the Druzes (Islam, Judaism, and Christianity), the Baha'i (the universal faith), the Mandaeans (Judaism and Christianity), and the Parsis (Mazdaism and Islam).

(10) ATHEISM. Atheists do not practise any religion (they are non-religious). Atheists do not believe in a Divinity. Atheists may be distinguished, however, so as to be considered (1) agnostic, or (2) anti-religious. Agnostics consider knowledge of the immaterial as impossible, while anti-religious atheists reject the existence of a spiritual life.

To sum up, the main religions of the world fall into the following categories.