Web Server
PHP Version
PHP Extensions

Fuel uses functionality that PHP defines as "extensions". To avoid any possible compatibility issues, Fuel only uses extensions that are part of the PHP code as documented on the PHP website. If extensions are used that are part of the PECL repository (which need to be installed manually by a system administrator), Fuel will use them if present, and work around it if not.

This is a list of extensions used, and the classes that use them:

Extension Used in Comments
fileinfo Upload Documentation.
Note that on Windows platforms, a manual installation of a DLL might be needed.
mbstring n/a Documentation.
If not present, the framework has no multibyte support. You can check the MBSTRING constant to see if your installation has multibyte support enabled.
mcrypt Crypt Documentation.
If not present, PHPSecLib is used to emulate its functionality.