PHP 4 has been with us (as "stable" release) since May 22nd,
2000. In the past 8 years it brought us lots of joy, but in the later years lots of pain. A better PHP, PHP 5, as been a better alternative for close to 3 years now so it's time to get rid of the old stuff that PHP 4 really is.
PHP 4 had quite some changes over the past years though. The main changes came with new mini releases:
4.1.0 (10 Dec 2001): The introduction of the super globals.
4.2.0 (22 Apr 2002): Register globals was turned off by default. The release announcement shouts "External variables (from the environment, the HTTP request, cookies or the web server) are no longer registered as global variables".
4.3.0 (27 Dec 2002): Introduces "CLI", PHP's Command Line Interface and streams.
4.4.0 (11 Jul 2005): Addresses the " reference issue ".
Now, more than 3 years after the last major PHP 4 release, it is time to die down. With hardly any support for OO, sub-standard XML support and generally lots of other suckyness as well, it's time to focus on the future: PHP 6. So please die PHP 4 - and quickly. Today, August 7th, 2008 is the last release of PHP 4 - PHP 4.4.9. After today there will be no more PHP 4 releases, regardless of whether there are security issues found in PHP 4. It's time to upgrade now .