PHP extensions are sets of instructions that add functionality to your PHP. Extensions can also be employed to recycle frequently used code. You can place a set of functions into one extension and instruct your projects to utilize the extension. Another use for PHP extensions is to improve efficiency and/or speed. Some processor intensive functions can be better coded as an extension, rather than as straight PHP code.

A list of the PHP extensions included with the Zend Server installation, and extensions added to the php.ini by the user, is displayed on the Configurations | PHP page. Use this page to view the status of all your extensions, to quickly and easily load and unload extensions, and to change directives.

See the PHP Extension List for a full breakdown of available extensions.