.php? use with mysql query

[Bryan St Clair]

I am able to pull info from my mysql from a page with a search feature.

I want to have a page pull info based on the url. Exampe:

www.domain.com/results.php?uid=33

This page would search a defined search in the php file for uid = 33 and return the results.

I am new to php, and have not found any writeups on the use of a '?' in a php url. Can someone point me to one please?

Thanks