Form Method Get ->php script

Lately I have been trying to learn how the form method get works and have figured out how to get a variable added to URL, but I can not figure out how then to get that variable (that is now part of the URL) into a variable for a php script. I searched several tutorial sites but didn't find anything (or maybe I am just slow...). Just as an example lets say that my URL after getting some form data appended to it is http://www.u.arizona.edu/~avr/admin1.php3?question=5. How do I make a perl script that has the variable question equal to 5? Thanks for any help If you want to reply personally, remove all numbers from my address. -Andrew Romero