Dr. Mahmoud Salam Zanati compiled a study on wearing the hijab and the mixing and segregation of the two sexes in Arab society. He wrote that Arabs during the Jahiliya times and until the Ummayyid period didn’t know of sexual segregation. The obligation of the veil was only applied to the women of the prophet because of their special state. Starting from the Abbassid era, sexual segregation prevailed and Arabs started obliging their women to wear the hijab.