Hypertext Preprocessor (PHP) is a cross platform open source server side scripting language that can be used to generate dynamic and interactive web pages. PHP scripts or codes can be embedded within HTML pages. When a request is sent for a PHP page, the server parses and executes the code and returns the output as plain HTML. PHP scripts can be written to interact with databases and include a host of database connectivity features providing support for a wide range of platforms such as MySQL, Microsoft SQL Server, Oracle, PostgreSQL etc. PHP can be used to create web applications ranging from personal websites to e-commerce applications and community web portals i.e. disucssion forums, blogs etc. Apart from web applications and server side scripting, PHP can be used for command-line scripting and client-side GUI application development.

PHP is based on an Object Oriented Architecture and most of its features, concepts and syntax are based on the C and Perl programming languages. Being an open source language, a large number of libraries and extensions, to extend its core functionalities, are available for download. PHP extensions include support for features such as XML parsing, compression utilities, dynamic generation of images, translation functions etc.

PHP scripts can run across operating systems such as Linux, Windows, Solaris, OpenBSD, Mac OSX etc and also provide support for all major web servers such as Apache, IIS, iPlanet etc.