What laserlight was trying to say was:
in Php4 there is a new set of "super globals", these are
$FILES
$SESSION;
$COOKIE
$SERVER
$POST
$GET
These are all arrays
(hope i didn't forget any)
So where you used to have a var being passed in the url it can now be access using the $GET['var_name'] array, conversly if you are using POST then the vars will be in the $POST array
Oh and yeah read the FAQ's as well, this may also help
HTH
GM