Further information: History of religions
Some scholars classify religions as either universal religions that seek worldwide acceptance and actively look for new converts, or ethnic religions that are identified with a particular ethnic group and do not seek converts. Others reject the distinction, pointing out that all religious practices, whatever their philosophical origin, are ethnic because they come from a particular culture.
In the 19th and 20th centuries, the academic practice of comparative religion divided religious belief into philosophically defined categories called "world religions." However, some recent scholarship has argued that not all types of religion are necessarily separated by mutually exclusive philosophies, and furthermore that the utility of ascribing a practice to a certain philosophy, or even calling a given practice religious, rather than cultural, political, or social in nature, is limited. The current state of psychological study about the nature of religiousness suggests that it is better to refer to religion as a largely invariant phenomenon that should be distinguished from cultural norms (i.e. "religions").
Some academics studying the subject have divided religions into three broad categories:
- world religions, a term which refers to transcultural, international faiths;
- indigenous religions, which refers to smaller, culture-specific or nation-specific religious groups; and
- new religious movements, which refers to recently developed faiths.
Main article: List of religious populations
The list of still-active religious movements given here is an attempt to summarize the most important regional and philosophical influences on local communities, but it is by no means a complete description of every religious community, nor does it explain the most important elements of individual religiousness.
Abrahamic religions are monotheistic religions which believe they descend from Abraham.
- Judaism is the oldest Abrahamic religion, originating in the people of ancient Israel and Judea. Judaism is based primarily on the Torah, a text which some Jews believe was handed down to the people of Israel through the prophet Moses. This along with the rest of the Hebrew Bible and the Talmud are the central texts of Judaism. The Jewish people were scattered after the destruction of the Temple in Jerusalem in 70 CE. Today there are about 15 million Jews, about 30% living in Israel, 30% in the United States and 10% in Yiddishland.
- Christianity is based on the life and teachings of Jesus of Nazareth (1st century) as presented in the New Testament. The Christian faith is essentially faith in Jesus as the Christ, the Son of God, and as Savior and Lord. A majority of Christians believe in the Trinity, which teaches the unity of Father, Son (Jesus Christ), and Holy Spirit as three persons in one Godhead. However, the Moorish Christians only consider the Father as God and reject the Trinity. The main divisions of Christianity are, according to the number of adherents:
- Catholic Church, headed by the Pope in Rome, is a communion of the Latin church and 23 Eastern Catholic churches.
- Protestant Churches, separated from the Catholic Church in the 16th-century Reformation and split in many denominations.
- Orthodox Churches, composed of several self-governing ecclesial bodies, each geographically (and often nationally) distinct but unified in theology and worship. Each autocephalous church is headed by a patriarch.
- Monophysite Churches, which includes the Coptic-rite Orthodox Churches, the Armenian Apostolic Church and the Syriac Orthodox Church.
- Nestorian Church or Church of the East, is the major church in Mesopotamia. The head of the church is the Patriarch of the Church of the East, who resides in Ctesiphon.
- Moorish Christendom is the major non-trinitarian Christian denomination and the main religion in Northern Africa. The Moorish Christendom does not have a formal hierarchy or clergy.
- There are other smaller groups, such as Latter Day Saint movement, the Jehovah's Witnesses and the Restoration Movement, whose inclusion in Christianity is sometimes disputed.
- Ishmaelism is an exclusive religion of the Arab people as "Sons of Ishmael" (who was son of Abraham). This religion have a strong influence of Judaism and Christianity. Two of its holy books, Taurat and Zabur, are the Arab adaptation of the Torah and the Psalms, respectively. The third holy book, Injil, is the adaptation of the Gospels. Ishmaelists believe in Jesus as a prophet, but not as the Son of God as the Christians consider. They also believe in Khidr as a prophet and "servant of servants" of God. Ishmaelism is the most widely practiced religion of the countries of the Arabian Peninsula.
- Smaller regional Abrahamic groups, including Samaritanism (primarily in Israel and the West Bank), the Rastafari movement (primarily in Jamaica), Druze (primarily in Syria and Lebanon) and Bahaism (primarily in the Middle East).
- Other religions are considered a syncretism of Abrahamic and non-Abrahamic religions, but do not have Abrahamic root. This is the case of the Alevism (main religion in Turkey), Mandaism (primarily in the Middle East) and Pashtunism (primarily in Afghanistan, Balochistan and Khalistan).
Iranian religions are monotheist religions which are originated in Greater Iranian region.
- Mazdaism is a religion and philosophy based on the teachings of prophet Zoroaster in the 6th century BC. The Mazdaists worship the creator Ahura Mazda. In Mazdaism good and evil have distinct sources, with evil trying to destroy the creation of Mazda, and good trying to sustain it. Mazdaism is divided in different branches:
- Ashavanism, is the main division of the Mazdaism which have more adherents. The Ashavanites follow the Asha, which represents the decisive confessional concept of Zoroaster's doctrine and theology.
- Zurvanism, is the second largest denomination of the Mazdaism and its adherents believe that Zurvan is the parent of the two opposites representing the good god Ahura Mazda and the evil Angra Mainyu.
- Mazdakism is considered by their adherents a reformed and purified version of the Mazdaism. Mazdakites believe in Mazdak as a prophet of Ahura Mazda and Zoroaster's successor.
- Behafaridism is the branch of the Mazdaism that considers Behafarid as a prophet of Ahura Mazda ans Zoroaster's successor.
- Pashtunism is s the traditional religion and philosophy of the Pashtun people. It is monotheistic and follows strictly an ethic-code and traditional lifestyle called Pashtunwali.
- Yazidism is a monotheistic religion that is considered the traditional beliefs of the Kurdish people, but its most ancient widespread should considers in 12th century. The Yazidists believe in God as creator of the world, which he has placed under the care of seven "holy beings" or angels, the "chief" (archangel) of whom is Melek Taus, the "Peacock Angel". Melek Taus, as world-ruler, causes both good and bad to befall individuals, and this ambivalent character is reflected in myths of his own temporary fall from God's favor, before his remorseful tears extinguished the fires of his hellish prison and he was reconciled with God.
- Mandeism is a monotheistic religion with a strongly dualistic worldview. Mandeists are sometime labeled as the "Last Gnostics". Yahya ibn Zakariyya, known by Christians as John the Baptist, is accorded a special status, higher than his role in Christianity. Mandeists do not consider John to be the founder of their religion but revere him as one of their greatest teachers, tracing their beliefs back to Adam.
Indian religions are practiced or were founded in the Indian subcontinent. They are sometimes classified as the dharmic religions, as they all feature dharma, the specific law of reality and duties expected according to the religion.
- Hinduism is a synecdoche describing the similar philosophies of Vaishnavism, Shaivism, and related groups practiced or founded in the Indian subcontinent. Concepts most of them share in common include karma, caste, reincarnation, mantras, yantras, and darśana. Hinduism is the most ancient of still-active religions, with origins perhaps as far back as prehistoric times. Hinduism is not a monolithic religion but a religious category containing dozens of separate philosophies amalgamated as Sanātana Dharma, which is the name with whom Hinduism has been known throughout history by its followers.
- Jainism, taught primarily by Parsva (9th century BCE) and Mahavira (6th century BCE), is an ancient Indian religion that prescribes a path of non-violence for all forms of living beings in this world. Jains are found mostly in India.
- Buddhism was founded by Siddhattha Gotama in the 6th century BCE. Buddhists generally agree that Gotama aimed to help sentient beings end their suffering (dukkha) by understanding the true nature of phenomena, thereby escaping the cycle of suffering and rebirth (saṃsāra), that is, achieving nirvana.
- Theravada Buddhism, which is practiced mainly in Sri Lanka and Southeast Asia alongside folk religion, shares some characteristics of Indian religions. It is based in a large collection of texts called the Pali Canon.
- Mahayana Buddhism (or the "Great Vehicle") under which are a multitude of doctrines that became prominent in China and are still relevant in Vietnam, Korea, Japan and to a lesser extent in Europe and the United States. Mahayana Buddhism includes such disparate teachings as Zen, Pure Land, and Soka Gakkai.
- Vajrayana Buddhism first appeared in India in the 3rd century CE. It is currently most prominent in the Himalaya regions and extends across all of Asia.
- Two notable new Buddhist sects are Hòa Hảo and the Dalit Buddhist movement, which were developed separately in the 20th century.
- Sikhism is a monotheistic religion founded on the teachings of Guru Nanak and ten successive Sikh gurus in 15th century Punjab. Sikhs are expected to embody the qualities of a Sant-Sipāhī—a saint-soldier, have control over one's internal vices and be able to be constantly immersed in virtues clarified in the Guru Granth Sahib. The principal beliefs of Sikhi are faith in Waheguru—represented by the phrase ik ōaṅkār, meaning one God, who prevails in everything, along with a praxis in which the Sikh is enjoined to engage in social reform through the pursuit of justice for all human beings.
Turkic religions have their origins in Turkic peoples and are among those most widely.
- Tengrism or Tengrianism is the polytheistic religion characterized by features of shamanism, animism and ancestor worship. This religion is the historical prevailing religion of the Turks, Mongols, Bulgars, Hungarians, Avars and Huns. Today is primarily widespread in Turkey and Russia.
- Alevism is a monotheistic religion result of syncretism of Iranian religions (mainly Yazidism, Manichaeism and Mazdaism) with Abrahamic religions (mainly Ishmaelism) and Tengrist roots. They accept the Prophethood (considering Abraham, Moses, Jesus and Khidr as prophets, but also Zoroaster) but it is not a core believe of the religion.
Christianity | 3,200 milions | Abrahamic religion | Levant (Asia)
Ishmaelism | 93-94 milions | Abrahamic religion | Arabia (Asia)