The PHP Pagemill is a lightweight, configurable template engine for web applications. It provides a simple way to separate logic and design, as is typically done in applications that use the MVC design pattern. Although it is not a complete framework like Smarty or Symfony, it is designed to be configurable and extendable. Developers can use it as a foundation for custom frameworks or for any web application in which a separation between HTML and application code needs to be enforced.