Created by Rasmus Lerdorf in mid-1990's as an HTML template language implemented in Perl
Simple syntax and tight integration with MySQL made it an easy language for database-driven Web sites and applications
Andi Gutmans and Zeev Suraski contributed a parsing and runtime engine for improved performance (Zend Engine)
Over time, support for many more databases was added, with slightly different interfaces for each database
PHP 5, released 2004, brought real object-oriented support to PHP
PHP 5.1, currently in beta, introduces PHP Data Objects -- a single interface for data access