PHP Question regarding include()

I have been using PHP for a few weeks now and have found it very useful. I am in the process of rewriting my website using PHP. I have a index.php, which imports a header.php and footer.php. But I want to call header.php with some variables defined in index.php. i.e. "header.php?title=homepage". I current have:

        include("header.php?headertitle=homepage&headersection=home");
in index.php. This is so each content page can set the title and 'section' for the header of each page.

and in header.php

           <title>Daniel's Website:<? $headertitle ?></title>

However when I load index.php in my web browser I get: Warning: Failed opening 'header.php?headertitle=homepage&headersection=home' for inclusion (include_path='.:/usr/local/lib/php') in /home/daniel/public_html/new/index.php on line 2 I think I need to use another function, but due to the fact I am new to PHP I am not sure what that would be, any assistance would be appreciated. Thanks, Daniel.