Initially used to produce dynamic web pages, is widely used in developing web pages and applications. It is mainly used embedded in HTML code, but starting from version 4.3.0 can be used in a "command line" (CLI), allowing the creation of independent applications.
It is one of the most important programming languages ??and open source web server side, there are versions available for most web servers and for all operating systems. According to statistics is installed on 20 million websites and 1 million web servers.(?? Is available in license PHP and Free Software Foundation considers to be a free software.)
On July 13, 2004 PHP 5 was released, the Zend Engine II, he brought a more pronounced object orientation and supporting more features of this type of programming.
PHP 5 brings more news from version 4: