PHP Compatibility and Hosting Quick-Install Applications
PHP is a popular and simple server scripting language that enables Web developers to embed dynamic content into Web pages. PHP 5 is enabled for all Linux hosting accounts. PHP 5 is enabled for Windows hosting accounts running IIS 7, only.
For information on migrating an existing hosting account, see Switching your hosting account operating system.
NOTE: In IIS 7, Value Applications applications requiring PHP 5 can not be installed on sub-domains or aliased domains which point to sub-directories.