World religion founded by the Prophet Muhammad (Peace Be Upon Him). Founded in the 7th century, Islam is the youngest of the three monotheistic world religions (with Judaism and Christianity). An adherent to Islam is a Muslim.

Believers Worldwide
In 1990 there were an estimated 935 million Muslims worldwide, fewer than one-fifth of whom were Arab. Islam is the principal religion of much of Asia, including Indonesia (which has the world's largest Muslim population), Afghanistan, Malaysia, Pakistan, Bangladesh, Azerbaijan, Turkmenistan, Uzbekistan, Tajikistan, Kyrghyzstan, Kazakhstan, Iran, Iraq, Syria, Jordan, the Arab states, and Turkey; in Africa, of Egypt, Algeria, Tunisia, Djibouti, Gambia, Guinea, Libya, Mali, Mauritania, Morocco, Niger, Senegal, Somalia, Sudan, with sizable populations also in Chad, Eritrea, Ethiopia, Ghana, Tanzania (where the island of Zanzibar is predominantly Muslim), and Nigeria.

In Europe, Albania is predominantly Muslim, and, historically, Bulgaria, Bosnia, Macedonia, and Georgia have had Muslim populations. Elsewhere in Europe, immigrant communities of Muslims from N Africa, Turkey, and Asia exist in France, Britain, and Germany. In the Americas the Islamic population has substantially increased in recent years, both from conversions and the immigration of adherents from other parts of the world; 20% of the population of Suriname is Muslim.

Islamic Beliefs
At the core of Islam is the Qur'an, believed to be the final revelation by a transcendent Allah to Muhammad, the Prophet of Islam; since the Divine Word was revealed in Arabic, this language is used in Islamic religious practice worldwide. Muslims believe in final reward and punishment, and the unity of the umma, the "nation" of Islam. Muslims submit to Allah through arkan ad-din, the five basic requirements or "pillars": shahadah, the affirmation that "there is no god but God, and Muhammad is the Messenger of God"; salah, the five daily ritual prayers; zakat, the giving of alms, also known as a religious tax; Sawm, the dawn-to-sunset fast during the lunar month of Ramadan; and hajj, the pilgrimage to Mecca. The importance of the hajj can hardly be overestimated: this great annual pilgrimage unites Islam and its believers from around the world.

The ethos of Islam is in its attitude toward Allah: to His will Muslims submit; Him they praise and glorify; and in Him alone they hope. However, in popular or folk forms of Islam, Muslims ask intercession of the saints, prophets, and angels, while preserving the distinction between Creator and creature. Islam views the Message of Muhammad as the continuation and the fulfillment of a lineage of Prophecy that includes figures from the Hebrew Scriptures and the New Testament, notably Adam, Noah, Abraham, Moses, David, and Jesus. Islamic law reserves a communal entity status for the ahl al-kitab, People of the Book, i.e., those with revealed religions, including Jews and Christians. Islam also recognizes a number of extra-Biblical prophets, such as Hud, Salih, Shuayb, and others of more obscure origin. The chief angels are Gabriel and Michael; devils are the evil jinn.

Other Islamic obligations include the duty to "commend good and reprimand evil," injunctions against usury and gambling, and a prohibition of alcohol and pork. Meat is permitted (halal) if the animal was ritually slaughtered. Jihad, the exertion of efforts for the cause of God, is a duty satisfied at the communal and the individual level. At the individual level, it denotes the personal struggle to be righteous and follow the path ordained by God. In Islam, religion and social membership are inseparable: the ruler of the community (caliph) has both a religious and a political status. The unitary nature of Islam, as a system governing relations between a person and God, and a person and society, helped the spread of Islam so that, within a century of the Prophet's death, Islam extended from Spain to India. The evolution of Islamic mysticism into organizational structures in the form of Sufi orders was also, from the 13th century onwards, one of the driving forces in the spread of Islam. Sufi orders were instrumental in expanding the realm of Islam to trans-Saharan Africa, stabilizing its commercial and cultural links with the Mediterranean and the Middle East, and to South East Asia.

Holidays and Honorifics
The original feasts of Islam are id al-fitr, corresponding to the breaking of the fast of Ramadan, and id al-Adha, coinciding with the pilgrimage to Mecca. Shiite Islam also celebrates id al-ghadir, the anniversary of Muhammad's declaration of Ali as his successor. Other Islamic holidays include Mawlid Nabawi, Muhammad's birthday, and al-isra wa-l-miraj, the anniversary of his miraculous journey to Jerusalem and ascension to Heaven. Among the Islamic religious honorifics are shaykh, a generic term refering to a religious scholar or a mystic master; qadi, a religious judge (handling particular cases); mufti, a religious authority who issues general legal opinions; and mullah, a synonym of shaykh used in the Persian-speaking world.

Interpretation of the Quran
The revealed word of Islam, the Qur'an, in a formal Arabic which became more archaic with time, required explication. A complement to the Qur'an is the Sunna, the spoken and acted example of the Prophet, collected as hadith. The Sunna is almost as important to Islam as the Qur'an, for in it lie the elaborations of Qu'ranic teaching essential to the firm establishment of a world religion. There are serious disagreements in the hadith, and interpretations of the Qur'an and the Sunna have varied so much as to be contradictory. These situations are resolved by reference to one of the most important of the sayings attributed to the Prophet, "My community will never agree in an error." This leeway also allowed Islam to expand by incorporating social, tribal, and ethnic traditions. For example, with the exception of inheritance and witness laws, Islamic rights and obligations apply equally to men and women. The actual situation of women is more a function of particular social traditions predating Islam than of theoretical positions.