What is PHP?

PHP (Hypertext Preprocessor) is an open-source scripting language and interpreter. It is used primarily on UNIX Web servers to create interactive and customized Web pages and is an alternative to Microsoft Active Server Page (ASP) technology. (Click here for more information regarding ASP)

When PHP script is embedded within a Web page, the Web server calls PHP to interpret and perform the operations specified in the PHP script. Web pages with embedded PHP script can use the file extensions .php, .php3 or .phtml.