PHP can be used on all major operating systems (Windows, UNIX, Mac And probably RISC) also with many others because this is cross platform open source programming language.
PHP is also many web servers like APACHE and many others like WAMP. People works as either module or CGI processor.
Above paragraph told me that using PHP, I have the freedom of selecting operating system and a web server. I have also the choice of using programming method. I can use procedural programming, Object oriented programming or mixture of both.[More..]