PHP

PHP is one of the most widely used back-end languages on the web. Much of the codebase of many of the world's top websites are written in PHP, including Facebook, Wikipedia and Yahoo. We use PHP for most of the back-end work that we do, and it powers most of the systems and frameworks that we employ including Drupal, Wordpress, Joomla, CodeIgniter, ExpressionEngine and vBulletin.