History

On July 13, 2004, PHP 5 was released powered by the new Zend Engine II. PHP 5 included new features such as:[7]

Currently, two major versions of PHP are being actively developed: 5.x and 4.4.x. On July 13, 2007, the PHP group announced that active development on PHP4 will cease by December 31, 2007, however, critical security updates will be provided until August 8, 2008.[8] PHP 6 is currently under development, and is slated to release in conjunction with the decommission of PHP 4. -Source