PHP is a cross-platform server side embedded script language, a functionally powerful language and interpreter. Whether it is installed as a module of a server or as an individual CGI procedure, a PHP script can visit files, execute commands or make connections on the server. And all these activities are properly guarded for the security of the system. The grammar of PHP borrows a lot from that of C, Java, and Perl. But they are well integrated with PHP’s own features. So, with PHP the web developers can build dynamic pages quickly. PHP can enlarge the functions of Web server, and help the Web server achieve optimal services of the back end extended interface.