Smarty is a template engine for PHP, facilitating the separation of presentation (HTML/CSS) from application logic. This implies that PHP code is application logic, and is separated from the presentation. The Smarty design was largely driven by these goals: clean separation of presentation from application code; a PHP backend and Smarty template frontend; compliment PHP, not replace it; fast development/deployment for programmers and designers; quick and easy to maintain; a syntax that is easy to understand, with no PHP knowledge required; flexibility for custom development; and security (insulation from PHP).