The MIME type application/x-httpd-php is used to denote the file type PHP. The category of this MIME type is "application".

PHP is a general-purpose scripting language that was developed for web development and is widely used for creating dynamic html web pages. It is usually run on a web server and can also be embedded into HTML. The web servers need to support PHP in order to be able to generate HTML pages from it. Hence servers are specially configured for PHP. However, since it is so commonplace in web development, PHP can be deployed in almost every web server, platform and operating system with relative ease. Deployments of PHP in its various versions are completely free of any charge.

After being created by one man in 1995, PHP is now being developed and maintained by The PHP Group that produces the main implementation of PHP that is taken as the de facto standard all across the planet. While PHP is free software, it is released not under a GNL GPU license but under its own PHP license. This is because there are some restrictions on the use of the term PHP. It now has CLI and GUI applications.