Topic: From punbb script help

I am new to php and I am curious how this bit of code works:

// Make sure no one attempts to run this script "directly"
if (!defined('PUN'))
        exit;

I have been looking for something/anything that would point to how this works.
It doesn't seem to be a function as there are no "includes" prior.
So what does define 'PUN".

Thanks in advance.

Re: From punbb script help

config.php i think

Re: From punbb script help

Motivated, the file you are looking at is the included file.

Re: From punbb script help

Thanks guys, I've finally got it figured out after being up all nite.
I like this : define
Very handy