PHP is evolving continuously. Do you know what the different versions of our favorite programming language brought us? After this talk, you will be informed about the most important new features and - maybe - reading the appendices at php.net is no boring idea anymore.

Performance is undoubtedly the biggest reason why you should upgrade your servers as soon as a stable version is released. [...] PHP 7 handles more than twice as many requests per second, which in practical terms will represent a 100% improvement on performance for Wordpress websites.

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Mark Jaquith posted in June 2010 that the WordPress core developers planned to drop support for PHP 4 in favour of PHP 5.2. He stated that also the developers of the Drupal and Joomla project made this decision.

The official support for PHP 5.2 ended in January 2011. In PHP 5.3 were probably some difficult backward compatibility issues. But as you can see: This decision - made in 2011 - is still valid, even if it is not easily testable anymore in case you'd like to guarantee the backwards compatiblity also for your plugins.

Let's talk this time about the most exciting new features that will be available when you upgrade to the next PHP version.