How was a URL like http://stackoverflow.com/posts/1807421/edit created in PHP?

Question

When you edit a question on stackoverflow.com, you will be redirected to a URL like this:

https://stackoverflow.com/posts/1807421/edit

Answer 1

As @mr-euro stated you can use mod_rewrite but front controller is a far better solution. You force every request to index.php and you write your application controlling in index.php.