PHP, which is a bacronym for PHP: Hypertext Preprocessor, is one of the most commonly used scripting languages that are available out there. Any site or Internet app created using PHP will run on a given web server provided that a PHP module is installed, which renders the language really universal and it isn’t really a surprise that there are a few million web servers that support it and hundreds of millions of PHP-driven sites hosted on them. PHP is preferred over HTML due to the fact that it enables you to develop a responsive website with a ton of different options. A PHP-based social network, for instance, will show different content to each visitor irrespective of the fact that the URL will remain unchanged. In contrast, HTML sites are static and the content on the pages can be updated only manually. Just like any other piece of software, PHP has different versions and the version that was used while creating a given website must be present on the server in order for the site to work properly.