Indexhibit Support

I wanted to know if I could add a code snippet to all (or some) pages within my site.

I think it's javascript, because it starts with this:
script type="text/javascript"

Is this possible? I wasn't sure if I could just add this to the text box area within the edit area of a page. It needs to be hidden from outside viewers.

It's possible...I do it in very rare circumstances but it will work.