To run any php file you need to install Apache web server on your localhost. Also you need to install MySQL server for any database programming. You can install these seperatly or there is easy way to achive the same by installing XAMPP.
XAMPP is an easy to install Apache distribution containing MySQL, PHP and Perl. [...]

PHP stands for “Hypertext Preprocessor“,  is a server-side scripting language used to create dynamic Web pages. This can be embedded to HTML pages. This is very easy scripting language compare to other scripting languags. The goal of the language is to allow Web developers to write dynamically generated pages quickly.
PHP supports many databases like MySQL, [...]