PHP is a server-side, cross-platform, HTML-embedded scripting language. Currently there are over half a million domains running PHP and it is freely available for download online from www.php.net. Much of PHP�s syntax is borrowed from C, Java and Perl with a couple of unique PHP-specific features thrown in. The goal of the language is to allow web developers to write dynamically generated pages quickly. PHP eliminates the need for numerous small cgi programs by allowing you to place simple scripts directly in your HTML files. It also makes it easier to manage large web sites by placing all components of a web page in a single html file.

For example, if you are creating an online catalog, you will most likely have a design template for all related catalog pages. Traditionally, this design is generated by hand in HTML and different data is presented within the template design. With PHP, one application can be used to generate all the pages required to display items from a database in the proper pages, in the right locations, and with the appropriate related content. This eliminates redundant page generation, simplifying maintenance. PHP also reduces the site down to a handful of template pages, with scripts that generate the rest of the site.

PHP is an excellent alternative to such similar programming solutions as Microsoft's proprietary scripting engine ASP and Allaire's rather expensive ColdFusion. As mentioned before, PHP is a cross-platform language. This doesn't stop with the core PHP code but can be extended to all of PHP's libraries and all code written in PHP. Neither ASP nor ColdFusion can make this claim. PHP has a large feature set which includes built-in support for numerous databases (including Access, LDAP, Oracle, and MSSQL), networking support, zip archiving ,and an excellent set of built-in functions. Furthermore, due in part to it being open source and freely available for download on the web, the language enjoys an active developing environment. Since the syntax structure borrows heavily from C, it is easy for even the novice programmer to learn the language. PHP is also the oldest HTML-embeded scripting language, giving it a head start on all the others.

If you are a content developer, you probably won�t want to learn PHP scripting by heart. But, it is nice to know how PHP can help you create more powerful web applications and user-friendly designs.

php is called hypertext preprocessor because php libraries are already compiled and processed. when any person request any php page in browser address bar that request first go to server for example Apache is running on that server. then server interpret php files and return back response in form of HTML. thats the reason php is called hypertext preprocessor.