Question: what are the 7 ahruf?
Answer: Bismika Allahuma, also states that at least according to one scholarly opinion there were seven ahruf because there were seven Arab tribes -- Quraysh, Hudhayl, Tameem, Hawaazin, Thaqeef, Kinaanah and Yemen -- each with there own dialects (lughaat) at the time the Quran was revealed.