In its traditional form, it is worn by women to maintain modesty and privacy from unrelated males. According to the Encyclopedia of Islam and Muslim World, modesty in the Quran concerns both men's and women's "gaze, gait, garments, and genitalia". The Qur'an instructs Muslim women to dress modestly. Some Islamic legal systems define this type of modest clothing as covering everything except the face and hands up to the wrists. These guidelines are found in texts of hadith and fiqh developed after the revelation of the Qur'an but, according to some, are derived from the verses (ayahs) referencing hijab in the Qur'an. Some believe that the Qur'an itself does not mandate that women wear hijab.