UNICODE representations in IDEA editor

Hello;

I have a question regarding display of unicode characters in IDEA's editor.
When I copy/paste a symbol: ? or \2791 it shows an eight ball. Omea can't
display it, it shows a square. Idea can show this character.

What I don't understand is where is that information stored? When I open
the java source file in another editor(emacs/slick edit--both in text and
hex view) I see a question. I see 3F which is a question '?'.

Does Idea keep my \2791 in a different place?

Thanks.