PHP is the programming language that WordPress runs on and newer versions of PHP are faster than the previous version. Therefore, for optimal performance, we want to be running the highest version of PHP our site, plugins and theme will support.
The WPAlpha hosting platform includes a tool that with automatically test your site and determine PHP version compatibility so you can more safely change or upgrade your PHP version. In this video, we walk you through the process of using our PHP testing tool to check for PHP compatibility before you change PHP versions and where to change PHP versions in the admin backend.