Shī‘a Islam, also Shi‘ite Islam or Shi‘ism (Arabic شيعة šīʿa), is the second largest denomination of the Islamic faith after Sunni Islam. Shias adhere to the teachings of Muhammad and the religious guidance of his family (who are referred to as the Ahl al-Bayt) or his descendents known as Shi'a Imams. Muhammad's bloodline continues only through his beloved daughter Fatima Zahra and cousin Ali which alongside the prophet's grandsons are the Ahl al-Bayt. Thus, Shi'as consider Muhammad's descendents as the true source of guidance while considering the first three ruling Sunni Caliph (the head of state in a Caliphate) a historic occurrence and not something attached to faith. The singular/adjective form is šīʿī (شيعي.) and refers to a follower of the faction of Imam Ali according to the Shia ideology.
Shia Islam, like Sunni Islam, has at times been divided into many branches; however, only three of these currently have a significant number of followers. The best known and the one with most adherents is the Twelvers (اثنا عشرية iṯnāʿašariyya) which have a large percentage in Iran 90% and Iraq (see also: Iraq Maps); the others are Ismaili, Sevener, and Zaidiyyah. Alawites and Druzes consider themselves Shias, although this is sometimes disputed by mainstream Shias. The Sufi orders among the Shias are the Alevi, Bektashi, Kubrawiya, Noorbakhshi, Oveyssi, Qizilbashi, Hamadani and Fatimid orders and denominations. Twenty percent of Turkey's population is Alevi while Lebanon and Syria have a large presence of Druze and Alawites.
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