HISTORY.
PHP is a general-purpose scripting language especially suited to web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1994. The PHP reference implementation is now produced by The PHP Group. PHP originally stood for Personal Home Page, but it now stands for the recursive initialism PHP: Hypertext Preprocessor.
PHP code is usually processed on a web server by a PHP interpreter implemented as a module, a daemon or as a Common Gateway Interface (CGI) executable. On a web server, the result of the interpreted and executed PHP code – which may be any type of data, such as generated HTML or binary image data – would form the whole or part of an HTTP response. Various web template systems, web content management systems, and web frameworks exist which can be employed to orchestrate or facilitate the generation of that response. Additionally, PHP can be used for many programming tasks outside of the web context, such as standalone graphical applications and robotic drone control. Arbitrary PHP code can also be interpreted and executed via command-line interface (CLI).
The standard PHP interpreter, powered by the Zend Engine, is free software released under the PHP License. PHP has been widely ported and can be deployed on most web servers on almost every operating system and platform, free of charge.
The PHP language evolved without a written formal specification or standard until 2014, with the original implementation acting as the de facto standard which other implementations aimed to follow. Since 2014, work has gone on to create a formal PHP specification.
As of January 2021, 72% of PHP websites use discontinued versions of PHP, i.e. PHP 7.2 or lower, which are no longer supported by The PHP Development Team. A large additional fraction uses PHP 7.3, which is only (up to December 6, 2021) “supported for critical security issues only. “Over 40% of all PHP websites use version 5.6 or older, that not even Debian supports (Debian 9 supported version 7.0 and 7.1).
INTRODUCTION.
What is PHP?
* PHP is an acronym for “PHP: Hypertext Preprocessor”.
* PHP is a widely-used, open source scripting language.
* PHP scripts are executed on the server.
* PHP is free to download and use.
What Can PHP Do?
* PHP can generate dynamic page content.
* PHP can create, open, read, write, delete, and close files on the server.
* PHP can collect form data.
* PHP can send and receive cookies.
* PHP can add, delete, modify data in your database.
* PHP can be used to control user-access.
* PHP can encrypt data.
Why PHP?
* PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.).
* PHP is compatible with almost all servers used today (Apache, IIS, etc.).
* PHP supports a wide range of databases.
* PHP is free. Download it from the official PHP resource: www.php.net.
* PHP is easy to learn and runs efficiently on the server side.