Dynamic pages can serve a variety of purposes. For example, websites run by content management systems allow a single source code file to load the content of many different possible pages. Content creators use a admin panel to submit the content for new pages into the CMS' database. The dynamic page can then load the material for any page in the database, based on parameters in the URL with which a visitor requests the page. Dynamic pages are also what let users log into websites to see personalized content.