is the largest denomination of Islam, followed by 87–90% of the world's Muslims, characterized by a greater emphasis upon the traditions of the prophet and his companions. Its name comes from the word Sunnah
, referring to the behaviour of the Islamic prophet, Prophet Muhammad. The differences between Sunni and Shia Muslims arose from a disagreement over the succession to Muhammad and subsequently acquired broader political significance, as well as theological and juridical dimensions. According to Sunni traditions, Muhammad designated his successor as Abu Bakr by commanding him to lead prayers when he was ill. The Muslim community later corroborated this by electing him as the first caliph. This contrasts with the Shia view, which holds that Muhammad announced his son-in-law and cousin Ali ibn Abi Talib as his successor, most notably at Ghadir Khumm. Political tensions between Sunnis and Shias continued with varying intensity throughout Islamic history and have been exacerbated in recent times by ethnic conflicts and the rise of Wahhabism.