Abu al-Aswad al-Du'ali

Abu al-Aswad ad-Duʾali, whose full name was ʾAbū al-Aswad Ẓālim ibn ʿAmr ibn Sufyān ibn Jandal ibn Yamār ibn Hīls ibn Nufātha ibn al-ʿĀdi ibn ad-Dīl ibn Bakr, surnamed ad-Dīlī, or ad-Duwalī, was an Arab tabi'i, the poet companion of Ali ibn Abi Talib and was one of the earliest, if not the earliest, Arab grammarians. He is known for writing the earliest treatise on Arabic grammar, through study of the Quran, explaining why he is sometimes known as the "Father of Arabic Grammar."