PHP or Hypertext Preprocessor
November 23, 2009PHP, or PHP: Hypertext Preprocessor, is a widely used, general-purpose scripting language that was originally designed for web development, to produce dynamic web pages. It can be embedded into HTML and generally runs on a web server, which needs to be configured to process PHP code and create web page content from it. It can be deployed on most web servers and on almost every operating system and platform free of charge. PHP is installed on over 20 million websites and 1 million web servers.
PHP was originally created by Rasmus Lerdorf in 1995 and has been in continuous development ever since. The main implementation of PHP is now produced by The PHP Group and serves as the de facto standard for PHP as there is no formal specification. PHP is free software released under the PHP License, which is incompatible with the GNU General Public License (GPL) because of restrictions on the use of the term PHP.
PHP has evolved to include a command line interface capability and can also be used in standalonegraphical applications.
 |
|
| Usual file extensions | .php, .phtml .php5 .phps |
|---|---|
| Paradigm | imperative, object-oriented |
| Appeared in | 1995 (1995) |
| Designed by | Rasmus Lerdorf |
| Developer | The PHP Group |
| Stable release | 5.2.11 / 5.3.1 (5.2.11: 2009-09-16; 2 months ago / 5.3.1: 2009-11-19; 3 days ago) |
| Preview release | 6.0.0-dev[1] |
| Typing discipline | Dynamic, weak |
| Major implementations | Zend Engine, Roadsend PHP, Phalanger, Quercus, Project Zero |
| Influenced by | C, Perl, Java, C++, Tcl[citation needed] |
| Influenced | PHP4Delphi, Falcon |
| Programming language | C |
| OS | Cross-platform |
| License | PHP License |
| Website | http://www.php.net/ |
PHP originally stood for personal home page. It began in 1994 as a set of Common Gateway Interface (CGI) binaries written in the C programming language by the Danish/GreenlandicRasmus Lerdorf. Lerdorf initially created these Personal Home Page Tools to replace a small set of Perl scripts he had been using to maintain his personal homepage. The tools were used to perform tasks such as displaying his résumé and recording how much traffic his page was receiving. He combined these binaries with his Form Interpreter to create PHP/FI, which had more functionality. PHP/FI included a larger implementation for the C programming language and could communicate with databases, enabling the building of simple, dynamic web applications. Lerdorf released PHP publicly on June 8, 1995 to accelerate bug location and improve the code. programmer This release was named PHP version 2 and already had the basic functionality that PHP has today. This included Perl-like variables, form handling, and the ability to embed HTML. The syntax was similar to Perl but was more limited, simpler, and less consistent.
Zeev Suraski and Andi Gutmans, two Israeli developers at the Technion IIT, 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. Afterwards, public testing of PHP 3 began, 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. They also founded Zend Technologies in Ramat Gan, Israel.
On May 22, 2000, PHP 4, powered by the Zend Engine 1.0, was released. As of August, 2008 this branch is up to version 4.4.9. PHP 4 is no longer under development nor will any security updates be released. On July 13, 2004, PHP 5 was released, powered by the new Zend Engine II. PHP 5 included new features such as improved support for object-oriented programming, the PHP Data Objects extension (which defines a lightweight and consistent interface for accessing databases), and numerous performance enhancements. In 2008, PHP 5 became the only stable version under development. Late static binding has been missing from PHP and has been added in version 5.3. PHP 6 is under development alongside PHP 5. Major changes include the removal of register_globals, magic quotes, and safe mode. The reason for the removals was that register_globals had given way to security holes, and magic quotes had an unpredictable nature, and was best avoided. Instead, to escape characters, magic quotes may be substituted with the addslashes() function, or more appropriately an escape mechanism specific to the database vendor itself like mysql_real_escape_string() for MySQL. Functions that will be removed in PHP 6 have been deprecated in PHP 5.3 and will produce a warning if used.
Many high-profile open-source projects ceased to support PHP 4 in new code as of February 5, 2008, because of the GoPHP5 initiative, provided by a consortium of PHP developers promoting the transition from PHP 4 to PHP 5.
PHP currently does not have native support for Unicode or multibyte strings; Unicode support will be included in PHP 6 and will allow strings as well as class, method and function names to contain non-ASCII characters.
It runs in both 32-bit and 64-bit environments, but on Windows the only official distribution is 32-bit, requiring Windows 32-bit compatibility mode to be enabled while using IIS in a 64-bit Windows environment. As of PHP 5.3.0, experimental x64 bit versions are available.
PHP is a general-purpose scripting language that is especially suited for web development. PHP generally runs on a web server. Any PHP code in a requested file is executed by the PHP runtime, usually to create dynamic web page content. It can also be used for command-line scripting and client-side GUI applications. PHP can be deployed on most web servers, many operating systemsplatforms, and can be used with many relational database management systems. It is available free of charge, and the PHP Group provides the complete source code for users to build, customize and extend for their own use. and
PHP primarily acts as a filter, taking input from a file or stream containing text and/or PHP instructions and outputs another stream of data; most commonly the output will be HTML. Since PHP 4, the PHP parser compiles input to produce bytecode for processing by the Zend Engine, giving improved performance over its interpreter predecessor.
Originally designed to create dynamic web pages, PHP now focuses mainly on server-side scripting, and it is similar to other server-side scripting languages that provide dynamic content from a web server to a client, such as Microsoft’s Active Server Pages, Sun Microsystems’ JavaServer Pages, and mod perl. PHP has also attracted the development of many frameworksrapid application development (RAD). Some of these include CakePHP, Symfony, CodeIgniter, and Zend Framework, offering features similar to other web application frameworks. that provide building blocks and a design structure to promote
The LAMP and WAMP architectures have become popular in the web industry as a way of deploying web applications. PHP is commonly used as the P in this bundle alongside Linux, Apache and MySQL, although the P may also refer to Python or Perl.
As of April 2007, over 20 million Internet domains were hosted on servers with PHP installed, and mod_php was recorded as the most popular Apache module. Significant websites are written in PHP including the user-facing portion of Facebook, Wikipedia (MediaWiki) Yahoo!,MyYearbook, Digg, Joomla, WordPress, YouTube in its early stages, Drupal and Tagged.
FOR TUTORIALS, PLEASE CLICK THIS YES TO PROCEED IN TUTORIALS
