The standard GET query as a link for each user is easy but ugly for the users and search engines.
// This looks UGLY
website.com/index.php?userid=43232
//This is what I want
website.com/coolUser
How to make a custom link for every user without creating folders all the time?
Simple way to make URL like that, using .htaccess (create .htaccess file and upload to your public_html / wwwdir)
Now, you can access http://yoursite.com/43232 OR http://yoursite.com/index.php?userid=43232