The script initially retrieves the list of all pages on the website (physical pages as well as pages in a database. e.g CMS). It then checks each link in each page against this list. The user may also specify a list of folders to ignore. This script can be usefull on large sites as it can be used to determine internal/external page links that are dead. The script can be easily extended to list pages that contain invalid links to images, javascript, css files etc.