Ahl al-Bayt (Arabic: أهل البيت, Persian: اهلِ بیت) is a phrase meaning, literally, "People of the House" or "Family of the House". Within the Islamic tradition, the term refers to the family of the Islamic prophet Muhammad.
In Shia Islam the Ahl al-Bayt are central to Islam and interpreters of the Quran and Sunnah. Shias believe they are successors of Muhammad and consist of Muhammad, Fatimah, Ali, Hasan, and Husayn (known collectively as the Ahl al-Kisa, "people of the mantle") and the Imams, the so-called Fourteen Infallibles. There are differing opinions on the scope and importance of Ahl al-Bayt.
In Sunni Islam, Muhammad's household refers to Muhammad himself; his wives and daughters, including Fatimah; his cousin and son-in-law Ali; and their two children, Hasan ibn Ali, Husayn ibn Ali, and all the descendants of Muhammad. Sometimes the descendants of his paternal uncles, Abu Talib and al-‘Abbas are included as well. Some Sunnis consider only the family up until Hasan ibn Ali and Husayn ibn Ali to be members of the Ahl al-Bayt. Bayt. The Ummayad Caliph, Muawiyah I, was the one to oppose Ali, member of the Ahlul Bayt, and cousin and son in law to Muhammad. Following Muawiyah I's rule, his successor and offspring, Yazid I, would be the one to murder Muhammad's grandson Husayn bin Ali during the Battle of Karbala.