According to Sunni traditions, Muhammad did not clearly designate a successor and the Muslim community acted according to his sunnah in electing his father-in-law Abu Bakr 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.
The adherents of Sunni Islam are referred to in Arabic as ahl as-sunnah wa l-jamāʻah ("the people of the sunnah and the community") or ahl as-sunnah for short. In English, its doctrines and practices are sometimes called Sunnism, while adherents are known as Sunni Muslims, Sunnis, Sunnites and Ahlus Sunnah. Sunni Islam is sometimes referred to as "orthodox Islam", though some scholars view this translation as inappropriate.
Sultan Salahuddin Abdul Aziz Mosque in Shah Alam, Selangor, Malaysia
Sunnī (Classical Arabic: سُنِّي/ˈsunniː/), also commonly referred to as Sunnīism, is a term derived from sunnah (سُنَّة/ˈsunna/, plural سُنَنsunan/ˈsunan/) meaning "habit", "usual practice", "custom", "tradition". In Arabic, the word is an adjective literally meaning "pertaining to the Sunnah". The Muslim use of this term refers to the sayings and living habits of the prophet Muhammad. In Arabic, this branch of Islam is referred to as ahl as-sunnah wa l-jamāʻah (Arabic: أهل السنة والجماعة), "the people of the sunnah and the community", which is commonly shortened to ahl as-sunnah (Arabic أهل السنة).