Quick Definition: Sunnis and Shias
Sunni Muslims and Shia Muslims (also known as Shiites) comprise the two main sects within Islam. Sunni and Shia identities first formed around a dispute over leadership succession soon after the death of the Prophet Muhammad in 632 A.D. Over time, however, the political divide between the two groups broadened to include theological distinctions and differences in religious practices as well.
While the two sects are similar in many ways, they differ over conceptions of religious authority and interpretation as well as the role of the Prophet Muhammad's descendants, for example.
For readers seeking more detail on the categories used in this report, Sunnis include followers of the Hanafi, Shafi, Maliki and Hanbali schools of Islamic jurisprudence as well as the Wahhabi or Salafi movement. Shias include Ithna Asharis (Twelvers), Ismailis, Zaydis, Alevis and Alawites.
There also are a few Muslim groups that are difficult to classify as either Sunni or Shia. These include Kharijites in Oman and the Nation of Islam movement in the United States, as well as the Druze, who are located primarily in and around Lebanon. Given the relatively small numbers of people associated with such groups, this report does not provide separate figures for them, but they are included in the overall Muslim population statistics.
Readers should also note that there is no separate estimate for Sufis, whose spiritual and mystical practices have a following among both Sunnis and Shias. There are no reliable figures on the proportion of Muslims worldwide who follow Sufi practices.
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