In Chapter 24 of the Quran, God tells both men and women to restrain their eyes from ogling at members of the opposite sex and to guard their private parts. Specific to women in this chapter is verse 32, which instructs women to “disclose not their beauty except that which is apparent thereof, and that they draw their head-coverings over their bosoms.”
The variations, however, of the dress are purely cultural. There is the burqa (or niqab), which is a full length dress or outer clothing that covers the head, face and body. The hijab, on the other hand, covers the head and neck, with a separate piece — like a shawl or long coat — covers the body. The face is not covered with the hijab. The Quranic injunction found in chapter 24 is more closely aligned with the hijab. Which style a Muslim woman chooses to wear depends on tradition and cultural variation.