Social diversity

I think social diversity is a good thing, because having lots of cultures (customs,knowledge and different ways of life) can improve our knowledge. Languages are part of the heritage of a culture and I think they should be protected. In the Earth we have 6,000 languages.
In social diversity we have linguistic diversity, that can be divided into 2 groups:
Official languages: are the ones that are recognised by the State, are protected and promoted.
Unofficial languages: are rare languages, they may be replaced by other language.
It’s also important that at schools teachers teach how to make children to accept other cultures and religions.