PHP costs you nothing. It is open-source software and doesn't need to purchase it for development.
Easy to use
PHP is easy to learn, compared to the others. A lot of ready-made PHP scripts are freely available in the market so, you can use them in your project or get some help from them.
PHP is embedded inside HTML in other codes, PHP pages are standard HTML pages that escape into PHP mode just when essential. When a client request this page, that page the web server preprocesses it.
PHP and MYSQL run native on every popular flavor of UNIX and Windows. HTTP servers run on one of these two classes of the operating systems.
PHP is pleasingly zippy in its execution. When compiled as an Apache module on the UNIX side.