Introduction PHP

PHP (PHP: Hypertext Preprocessor) is a reflective programming language originally designed for producing dynamic Web pages and remote application software.[1] PHP is used mainly in server-side scripting, but can be used from a command line interface or in standalone graphical applications.

The sole implementation is produced by The PHP Group and released under the PHP License. It is considered to be free software by the Free Software Foundation. This implementation serves to define a de facto standard for PHP, as there is no formal specification.

PHP was written as a set of CGI binaries in the C programming language by the Danish/Greenlandic programmer Rasmus Lerdorf in 1994, to replace a small set of Perl scripts he had been using to maintain his personal homepage.[2] Lerdorf initially created PHP to display his résumé and to collect certain data, such as how much traffic his page was receiving. “Personal Home Page Tools” was publicly released on June 8, 1995 after Lerdorf combined it with his own Form Interpreter to create PHP/FI (this release is considered PHP version 2).[3][4]

Zeev Suraski and Andi Gutmans, two Israeli developers at the Technion – Israel Institute of Technology, rewrote the parser in 1997 and formed the base of PHP 3, changing the language’s name to the recursive initialism “PHP: Hypertext Preprocessor”. The development team officially released PHP/FI 2 in November 1997 after months of beta testing. Public testing of PHP 3 began immediately and the official launch came in June 1998. Suraski and Gutmans then started a new rewrite of PHP’s core, producing the Zend Engine in 1999.[5] They also founded Zend Technologies in Ramat Gan, Israel, which actively manages the development of PHP.

In May 2000, PHP 4, powered by the Zend Engine 1.0, was released. The latest version as of December 2006 is 4.4.4. PHP 4 is currently still supported by security updates for those applications that require it.

On July 13, 2004, PHP 5 was released, powered by the new Zend Engine II. PHP 5 included new features such as:[6]

* Robust support for Object-Oriented Programming
* The PHP Data Objects extension, which defines a lightweight and consistent interfaces for accessing databases
* Performance enhancements taking advantage of the new engine
* Better support for MySQL through a completely rewritten extension
* Embedded support for SQLite
* Integrated SOAP support
* Data iterators
* Error handling through Exceptions

PHP 5.2.0 was released in November 2006.