The minimal WordPress server requirements are listed below:

• PHP 4.2.x or above - http://php.net
• MySQL 4.0 or above - http://mysql.org
• Apache 1.13.19 or above - http://apache.org

You can find more comprehensive information about this in the official WordPress documentation at:

http://wordpress.org/about/requirements/

SiteGround servers are fully optimized to meet all WordPress requirements and to provide the best hosting environment for it.