Rasmus Lerdorf, a Danish programer in 1995, first developed the language when he created a set of Perl scripts to maintain his personal homepage. The scripts he developed displayed his resume and recorded his web-page traffic. Two Israeli developers, Zeev Suraski and Andi Gutmans, rewrote PHP's core and developed the Zend Engine by 1999. The Zend engine is a highly optimized execution engine that supports incorporating plug-in modules such as debuggers, performance boosters and custom loaders to dynamically extend PHP for a broader range of functionality, besides providing memory and resource management; transforming PHP as a full-featured development language.
Apart from Zend, PHP has also attracted other frameworks such as CakePHP, Symfony, and CodeIgniter, all providing a robust structure and promoting rapid application development (RAD).
The language is in a continuous state of evolution and development, with the latest versions adding static binding (version 5.3)and the PHP6 set to support unicode. The PHP Group now sets the de facto standard for PHP, providing the complete source code for users to build, customize and extend for their own use.
The open-source nature and ease of use has made PHP the most popular server-side scripting language in the world today. Over 20 million Internet domains now have web services hosted on servers with PHP installed, and 75 percent of all web servers have PHP installed. Most of the popular web content management systems such as MediaWiki, Joomla, WordPress, Drupal and Moodle are written in PHP as are the user interfaces of popular websites such as Wikipedia, Facebook and Digg.
PHP is now the dominant use in the "P" of the LAMP or WAMP architecture in widespread use in the web development industry. While LAM stands for Linux, Apache and MySQL, and WAM stands for Windows, Apache and MySQL, the "P" may refer to Python, Perl, or PHP.