URL of calling page

I believe there's a way in PHP to get the URL of the page that called the current page but can't find it. Is there such a function? Or would I have to use another script (like Javascript)? What I mean is if I click on a link on index.html to jeremiah.php I can call the function and find out I just came from index.html (and not henry.php or fred.php). Thank you. Allan Cleaveland Webmaster and Computer Technician Math Department Univeristy of Arkansas