Hair Is A Woman's Crowning Glory
Is there any question that a woman's hair is an essential element of her beauty? Think about all those shampoo commercials where a woman seductively whips her hair about--no doubt they are playing on the attractiveness of luxurious locks.
The sages recognized the significance of hair to a woman's beauty and the role that beauty plays in married life. In the Talmud (Berachot 24a), a married woman's hair is defined as ehrva, those parts of the body that are kept covered for reasons of modesty.
The practice of women covering their hair was once a societal norm (as it still is in many non-Western countries). With the changing standards of fashion and modesty, however, different forms of hair covering are seen in the Jewish community.
In some communities, women only cover their hair in synagogue or during times of prayer/ritual, while other women may wear a hat or bandana with their own hair flowing out.
In other communities, women will wear hats or scarves with all of their hair carefully tucked out of sight. Wigs (called sheitels) are also common in such communities.
Among some sects of Chassidim, women keep their hair extremely short and wear both a wig and a hat.
The mitzvah of covering one's hair is known as kisui rosh.