Hijab Requirement

The study of women in Islam deals with the attitudes and beliefs about the roles and add responsibilities of women within the religion of Islam. The complex relationship between women and Islam is defined by both Islamic texts and the history and culture of the Muslim world.

Hijab is the Quranic requirement that Muslims, both male and female, dress and behave modestly. The most important Quranic verse relating to hijab is sura 24:31, which says, 

"And tell the believing women to lower their gaze and guard their private parts and not to display their adornment except that which ordinarily appears thereof and to draw their headcovers over their chests and not to display their adornment except to their [maharim]..."

Islamic scholars agree that a woman should act and dress in a way that does not draw sexual attention to her when she is in the presence of someone of the opposite sex. Some islamic scholars[who?] specify which areas of the body must be covered; most of these require that everything besides the face and hands be covered, and some require all but the eyes to be covered, using garments such as chadors or burqas.[citation needed] Most mainstream scholars say that men, in contrast, should cover themselves from the navel to the knees. see more


source: http://en.wikipedia.org/wiki/Women_and_Islam#Dress_code