ExpressionEngine is an open source, flexible, and feature-rich content management platform that empowers hundreds of thousands of individuals and organizations around the world to easily manage their web site.
PHP: Hypertext Preprocessor is a server-side scripting language designed for Web development, but also used as a general-purpose programming language. PHP code may be embedded into HTML code, or it can be used in combination with various web template systems, web content management systems, and web frameworks.