PHP, which is a meta-acronym for PHP: Hypertext Preprocessor, is among the most widely used open-source server-side programming languages available out there. Any website or app built with PHP will run on a given web server provided that a PHP module is installed, which renders the language really universal and it’s scarcely surprising that there are actually a few million servers that support it and hundreds of millions of PHP sites running on them. PHP is preferred over HTML due to the fact that it permits you to develop a dynamic site with a lot of options. A PHP-based community site, for example, will display unique content to each visitor despite the fact that the URL will not change. By contrast, HTML-based sites are static and the page content can be modified only manually. Like any other software program, PHP has different versions and the version that was used while developing a given website must be present on the web server in order for the site to run flawlessly.