I can't think of any articles that have been written about this. $HTTP_GET_VARS is just an associative array holding all of the values passed to the script in the address.
So using the address I'm looking at while typing this my $HTTP_GET_VARS would look like this:
$HTTP_GET_VARS["num"] = 5
$HTTP_GET_VARS["id"] = 10878
$HTTP_GET_VARS["loc"] = 0
$HTTP_GET_VARS["thread"] = 10878
So if for some reason I couldn't access these variables using $num, $id, $log, $thread then I could make sure that I was getting the proper values by using the information in the $HTTP_GET_VARS array. It also makes passing these variables to functions much easier.
