Shī‘ah

Shia (/ˈʃiːə/; Arabic: شيعة‎‎ Shīʿah, from Shīʻatu ʻAlī, followers of Ali) is a branch of Islam which holds that the Islamic prophet Muhammad designated Ali ibn Abi Talib as his successor (Imam). Shia Islam primarily contrasts with Sunni Islam, whose adherents believe that Muhammad did not appoint a successor. Instead they consider Abu Bakr (who was appointed Caliph through a Shura, i.e. consensus) to be the correct Caliph.

Adherents of Shia Islam are called Shias of Ali, Shias or the Shi'a as a collective or Shi'i individually. Shia Islam is the second-largest branch of Islam: in 2009, Shia Muslims constituted 10–13% of the world's Muslim population.Twelver Shia (Ithnā'ashariyyah) is the largest branch of Shia Islam. In 2012 it was estimated that perhaps 85 percent of Shias were Twelvers.

Shia Islam is based on the Quran and the message of Muhammad attested in hadith, and on hadith taught by their Imams. Shia consider Ali to have been divinely appointed as the successor to Muhammad, and as the first Imam. The Shia also extend this "Imami" doctrine to Muhammad's family, the Ahl al-Bayt ("the People of the House"), and some individuals among his descendants, known as Imams, who they believe possess special spiritual and political authority over the community, infallibility, and other divinely-ordained traits. Although there are myriad Shia subsects, modern Shia Islam has been divided into three main groupings: Twelvers, Ismailis and Zaidis, with Twelver Shia being the largest and most influential group among Shia.

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