What Is PHP

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∟What Is PHP

This section describes what is PHP language and what are main features supported in PHP.

What Is PHP? PHP stands for PHP: Hypertext Preprocessor, a recursive acronym. It is mainly a Web server side scripting language. But it can also be used for other purposes.

PHP was originally created by Rasmus Lerdorf in 1995 as a simple Web page generation tool named as PHP/FI (Personal Home Page/Forms Interpreter). Today it becomes the number one of server side scripting languages. Here is a comparison of number of matches on Google for different popular script key words:

Key words             Number of matches

"PHP scripting"         400,000
"perl scripting"        371,000
"ASP.NET scripting"      40,100
"ASP scripting"          30,900
"JSP scripting"          17,500

Main features of PHP:

Web application features - PHP support most commonly used Web application features like: HTTP Cookie, Session, File Upload, etc.
CLI (Command-Line Interface)- PHP is commonly used to write Web applications to be integrated to Web servers using the Common Gateway Interface (CGI). But PHP can also be used to write standalone applications to be executed by the CLI (Command-Line Interface).
Data types - PHP supports many data types like other programming languages: signed and unsigned integers, floating numbers, strings, resources, null, etc.
File I/O - PHP supports most commonly used file I/O features like local file and path management, remote resource access using Internet protocols like HTTP and FTP.
Safe mode - PHP supports a safe mode with many built-in functions restricted or disabled.
Pre-compilation - PHP Web applications are usually deployed in source code, which will be interpreted on-the-fly when Web requests arrive to the server. But PHP Web applications can also be pre-compiled and deployed in executable format to speed up Web requests response time.
Object-oriented programming - PHP supports object-oriented programming features like object references, private and protected member variables and methods, abstract and final classes and methods, constructors and destructors, interfaces, etc.
Built-in modules - The standard PHP build comes with many free and open source libraries included as built-in modules for calendar dates handling, FTP protocol support, XML processing, encryption and decryption, ODBC support, ZIP support, regular expression support, etc.
Extensions - A large collection of PHP extensions are available to add functionalities to the standard PHP build. Examples of PHP extensions are Windows API, process management on Unix OS, multibyte string support, cURL (client-side URL transfer), image manipulation, data compression, database access, Web service, etc.

PHP major releases:

8.0   26 November 2020
7.0   3 December 2015
6.x   Not released
5.6   28 August 2014
5.4   1 March 2012
5.3   30 June 2009
5.0   13 July 2004
4.0   22 May 2000
3.0   6 June 1998
2.0   1 November 1997
1.0   8 June 1995