What are the minimum requirements of Hijab (Islamic modest dress) for a Muslim woman?

Answer

Woman should conceal all her body (including arms and legs) and hair from a man who is non-Mahram, and as an obligatory precaution, she should conceal herself even from a Na-baligh boy who is able to discern between good and evil, and could probably be sexually excited. But she can leave her face and hands upto wrists uncovered in the presence of Na-Mahram, as long as it does not lead him to casting a sinful, evil glance or her to doing something forbidden; for in both these cases, she must cover them.