Hijab or ħijāb (حجاب) is the Arabic term for "cover" (noun), based on the root حجب meaning "to veil, to cover (verb), to screen, to shelter"
The Quran instructs Muslims to dress in a modest way. In the Quran, Allah speaks about the quran speaks about men's hijab, then only women.The following verses are generally interpreted as applying to all Muslim men and women.
Surah 24 An- Nur, verse 31 :
And say to the believing women that they should lower their gaze and
guard their modesty; that they should not display their beauty and
ornaments except what (must ordinarily) appear thereof; that they should
draw their veils over their bosoms and not display their beauty except
to their husbands, their fathers, their husband's fathers, their sons,
their husbands' sons, their brothers or their brothers' sons, or their
sisters' sons, or their women, or the slaves whom their right hands
possess, or male servants free of physical needs, or small children who
have no sense of the shame of sex; and that they should not strike their
feet in order to draw attention to their hidden ornaments. And O ye
Believers! turn ye all together towards Allah, that ye may attain Bliss.
According to Dr Zakir Naik's speech in one of his Islamic talk, he described about the 6 main rules of approved hijab in Islam, which are:
It should not be transparent
Should not be tight or showing ur body figures and curves
It should not be glamorous that it attracts the opposites
Every part should be covered except for hands and face
It should not resembles the non-believers trend eg: wearing cross
It should not be similar or resembles the male's outfit
In Malaysia, the headscarf is known as a tudung.