Ahl al-Bayt

Ahl al-Bayt () is an Arabic phrase that refers primarily to the family of the prophet Muhammad. It sometimes also refers to the family of the prophet Ibrahim. 
In Shia Islam, the term refers to Muhammad, his daughter, Fatimah; his son-in-law, Ali; and their children, Hasan and Husayn. Twelver Shias include their Twelve Imams in the Ahl al-Bayt as well, whereas Zaydis and Ismailis include their imams in Ahl al-Bayt.
In Sunni Islam, the term refers to Muhammad; his wives, his children; and his grandchildren. In some other traditions, Ahl al-Bayt is used for the Banu Hashim clan.
In the Quran, Ahl al-Bayt has been used as a term of respect for wives.