what's the best way to share variables between main script and template files

[GZ Dark]

Hello,list,

Give my main srcipt is index.cgi,it require the two files of "header" and 
"footer" which are HTML templates.
Where in index.cgi:
use "header";

some logic codes...

use 'footer";


Then it'll generate a dynamic page.

My question is,how can I share the variables defined in the index.cgi 
between index.cgi and the two templates?

For example,I have a var in the index.cgi:

our %hash = (...);

then in the template files,I can see it by:

our $hash;
<br>$hash{'key1'}</br>

But is it the best way to use global vars for the sharing under modperl?is 
there any other good way?Thanks.