PHP is a widely-used, open source scripting language that is especially suited for website development. PHP code is executed on the web server, and the result is returned to the visitors browser as plain HTML.
PHP forms the basis of practically all of the commonly used website software on the internet, powering applications such as WordPress, Drupal and Joomla.
However, as new versions of PHP are released some of the code that has been used to write these applications is not updated as frequently. Therefore there may be occasions when you may want to use an "older" version of PHP to power your website.
Also certain applications require specific PHP extensions which we do not enable by default. We allow you full control over what extensions are enabled in the particular version of PHP that you select.
The "Select PHP Version" is found under the SOFTWARE section of cPanel.
From here you can also see What PHP extensions are enabled in my version of PHP?