Orthodox Christianity: The oldest established eastern form of Christianity, the Holy Orthodox Church, has a ceremonial head in the Bishop of Constantinople (Istanbul), also known as a Patriarch, but its various regional forms (e.g., Greek Orthodox, Russian Orthodox, Serbian Orthodox, Ukrainian Orthodox) are autocephalous (independent of Constantinople's authority, and have their own Patriarchs). Orthodox churches are highly nationalist and ethnic. The Orthodox Christian faith shares many theological tenets with the Roman Catholic Church, but diverges on some key premises and does not recognize the governing authority of the Pope.
Protestant Christianity: Protestant Christianity originated in the 16th century as an attempt to reform Roman Catholicism's practices, dogma, and theology. It encompasses several forms or denominations which are extremely varied in structure, beliefs, relationship to state, clergy, and governance. Many protestant theologies emphasize the primary role of scripture in their faith, advocating individual interpretation of Christian texts without the mediation of a final religious authority such as the Roman Pope. The oldest Protestant Christianities include Lutheranism, Calvinism (Presbyterians), and Anglican Christianity (Episcopalians), which have established liturgies, governing structure, and formal clergy. Other variants on Protestant Christianity, including Pentecostal movements and independent churches, may lack one or more of these elements, and their leadership and beliefs are individualized and dynamic.
Hinduism - Originating in the Vedic civilization of India (second and first millennium B.C.), Hinduism is an extremely diverse set of beliefs and practices with no single founder or religious authority. Hinduism has many scriptures; the Vedas, the Upanishads, and the Bhagavad-Gita are among some of the most important. Hindus may worship one or many deities, usually with prayer rituals within their own home. The most common figures of devotion are the gods Vishnu, Shiva, and a mother goddess, Devi. Most Hindus believe the soul, or atman, is eternal, and goes through a cycle of birth, death, and rebirth (samsara) determined by one's positive or negative karma, or the consequences of one's actions. The goal of religious life is to learn to act so as to finally achieve liberation (moksha) of one's soul, escaping the rebirth cycle.
Islam - The third of the monotheistic Abrahamic faiths, Islam originated with the teachings of Muhammad in the 7th century. Muslims believe Muhammad is the final of all religious prophets (beginning with Abraham) and that the Qu'ran, which is the Islamic scripture, was revealed to him by God. Islam derives from the word submission, and obedience to God is a primary theme in this religion. In order to live an Islamic life, believers must follow the five pillars, or tenets, of Islam, which are the testimony of faith (shahada), daily prayer (salah), giving alms (zakah), fasting during Ramadan (sawm), and the pilgrimage to Mecca (hajj).
Basic Groupings
The two primary branches of Islam are Sunni and Shia, which split from each other over a religio-political leadership dispute about the rightful successor to Muhammad. The Shia believe Muhammad's cousin and son-in-law, Ali, was the only divinely ordained Imam (religious leader), while the Sunni maintain the first three caliphs after Muhammad were also legitimate authorities. In modern Islam, Sunnis and Shia continue to have different views of acceptable schools of Islamic jurisprudence, and who is a proper Islamic religious authority. Islam also has an active mystical branch, Sufism, with various Sunni and Shia subsets.
Sunni Islam accounts for over 75% of the world's Muslim population. It recognizes the Abu Bakr as the first caliph after Muhammad. Sunni has four schools of Islamic doctrine and law - Hanafi, Maliki, Shafi'i, and Hanbali - which uniquely interpret the Hadith, or recorded oral traditions of Muhammad. A Sunni Muslim may elect to follow any one of these schools, as all are considered equally valid.
Shia Islam represents 10–20% of Muslims worldwide, and its distinguishing feature is its reverence for Ali as an infallible, divinely inspired leader, and as the first Imam of the Muslim community after Muhammad. A majority of Shia are known as "Twelvers," because they believe that the 11 familial successor imams after Muhammad culminate in a 12th Imam (al-Mahdi) who is hidden in the world and will reappear at its end to redeem the righteous.
Variants
Ismaili faith: A sect of Shia Islam, its adherents are also known as "Seveners," because they believe that the rightful seventh Imam in Islamic leadership was Isma'il, the elder son of Imam Jafar al-Sadiq. Ismaili tradition awaits the return of the seventh Imam as the Mahdi, or Islamic messianic figure. Ismailis are located in various parts of the world, particularly South Asia and the Levant.
Alawi faith: Another Shia sect of Islam, the name reflects followers' devotion to the religious authority of Ali. Alawites are a closed, secretive religious group who assert they are Shia Muslims, although outside scholars speculate their beliefs may have a syncretic mix with other faiths originating in the Middle East. Alawis live mostly in Syria, Lebanon, and Turkey.
Druze faith: A highly secretive tradition and a closed community that derives from the Ismaili sect of Islam; its core beliefs are thought to emphasize a combination of Gnostic principles believing that the Fatimid caliph, al-Hakin, is the one who embodies the key aspects of goodness of the universe, which are, the intellect, the word, the soul, the preceder, and the follower. The Druze have a key presence in Syria, Lebanon, and Israel.
Jainism - Originating in India, Jain spiritual philosophy believes in an eternal human soul, the eternal universe, and a principle of "the own nature of things." It emphasizes compassion for all living things, seeks liberation of the human soul from reincarnation through enlightenment, and values personal responsibility due to the belief in the immediate consequences of one's behavior. Jain philosophy teaches non-violence and prescribes vegetarianism for monks and laity alike; its adherents are a highly influential religious minority in Indian society.
Judaism - One of the first known monotheistic religions, likely dating to between 2000–1500 B.C., Judaism is the native faith of the Jewish people, based upon the belief in a covenant of responsibility between a sole omnipotent creator God and Abraham, the patriarch of Judaism's Hebrew Bible, or Tanakh. Divine revelation of principles and prohibitions in the Hebrew Scriptures form the basis of Jewish law, or halakhah, which is a key component of the faith. While there are extensive traditions of Jewish halakhic and theological discourse, there is no final dogmatic authority in the tradition. Local communities have their own religious leadership. Modern Judaism has three basic categories of faith: Orthodox, Conservative, and Reform/Liberal. These differ in their views and observance of Jewish law, with the Orthodox representing the most traditional practice, and Reform/Liberal communities the most accommodating of individualized interpretations of Jewish identity and faith.
Shintoism - A native animist tradition of Japan, Shinto practice is based upon the premise that every being and object has its own spirit or kami. Shinto practitioners worship several particular kamis, including the kamis of nature, and families often have shrines to their ancestors' kamis. Shintoism has no fixed tradition of prayers or prescribed dogma, but is characterized by individual ritual. Respect for the kamis in nature is a key Shinto value. Prior to the end of World War II, Shinto was the state religion of Japan, and bolstered the cult of the Japanese emperor.
Sikhism - Founded by the Guru Nanak (born 1469), Sikhism believes in a non-anthropomorphic, supreme, eternal, creator God; centering one's devotion to God is seen as a means of escaping the cycle of rebirth. Sikhs follow the teachings of Nanak and nine subsequent gurus. Their scripture, the Guru Granth Sahib - also known as the Adi Granth - is considered the living Guru, or final authority of Sikh faith and theology. Sikhism emphasizes equality of humankind and disavows caste, class, or gender discrimination.
Taoism - Chinese philosophy or religion based upon Lao Tzu's Tao Te Ching, which centers on belief in the Tao, or the way, as the flow of the universe and the nature of things. Taoism encourages a principle of non-force, or wu-wei, as the means to live