Question

why universal declaration of human rights are important

Answer 1

Even though it is not a legally binding document, UDHR was the first step in creation of the International Bill of Rights. So, it's political importance should not be neglected: It was the first time in human history that state officials from different cultures, with different religious or ethical convictions, agreed upon the list of individual (and collective) rights that should be guaranteed to everyone under their jurisdiction.

There are those who claim that, though the document itself is not legally binding, (some of) the rights it contains have become a part of international customary law. I do not find their arguments convincing, but I do think that it might be important as an interpretative means of the two Covenants of 1966. and other relevant human rights documents.

Answer 2

it's important to aware the public about their power
it's important so that none's dignity is hurt.
it's important for people to seek equality amd justice