Welcome to another video from Yenkna PCs. This time we're gonna look at yet
another website language called PHP. I'm gonna let my A.I. take over. Here you go.
Take it away. PHP is a server-side scripting language designed primarily
for web development but also used as a general-purpose programming language.
Originally created by Rasmus Lerdorf in 1994, the PHP reference implementation
is now produced by The PHP Development Team. PHP originally stood for Personal
Home Page, but it now stands for the recursive acronym PHP: Hypertext
Preprocessor. PHP code may be embedded into HTML or HTML5 markup, or it can be
used in combination with various web template systems,
web content management systems and web frameworks. PHP code is usually processed
by a PHP interpreter implemented as a module in the web server or as a Common
Gateway Interface (CGI) executable. The web server software combines the
results of the interpreted and executed PHP code, which may be any type of data,
including images, with the generated web page. PHP code may also be executed with
command-line interface (CLI) and can be used to implement
standalone graphical applications. 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,
leaving the canonical PHP interpreter as a de facto standard. Since 2014 work has
gone on to create a formal PHP specification. Early History: PHP
development began in 1995 when Rasmus Lerdorf wrote several
Common Gateway Interface (CGI) programs in C, which he used to maintain his
personal homepage. He extended them to work with web forms and to communicate
with databases, and called this implementation "Personal Home Page/Forms
Interpreter" or PHP/FI. PHP/FI could help to build simple, dynamic web
applications. To accelerate bug reporting and to improve the code, Lerdorf
initially announced the release of PHP/FI as "Personal Home Page Tools (PHP
Tools) version 1.0" on the Usenet discussion group comp.infosystems.www.authoring.cgi
on June 8, 1995. This release already had the basic functionality that PHP has
as of 2013. This included Perl-like variables,
form handling, and the ability to embed HTML. The syntax resembled that of Perl but was simpler,
more limited and less consistent. Lerdorf did not intend the early PHP to
become a new programming language, but it grew organically, with Lerdorf noting in
retrospect: "I don't know how to stop it, there was never any intent to write a
programming language I have absolutely no idea how to write a programming
language, I just kept adding the next logical step
on the way." A development team began to form and, after months of work and beta
testing, officially released PHP/FI 2 in November 1997. The fact that PHP
lacked an original overall design but instead developed organically has led to
inconsistent naming of functions and inconsistent ordering of their parameters. In some
cases, the function names were chosen to match the lower-level libraries which PHP was
"wrapping", while in some very early versions of PHP the length of the function names was
used internally as a hash function, so names were chosen
to improve the distribution of hash values. PHP 3 and 4:
PHP 3.0 is the successor of PHP/FI 2.0 . Zeev Suraski and Andi Gutmans rewrote
the parser in 1997 and formed the base of PHP 3, changing the language's name to
the recursive acronym PHP: Hypertext Preprocessor. 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,
Zend Engine 1.0, was released. As of August 2008 this branch reached version 4.4.9.
PHP 4 is no longer under development nor will any security
updates be released. PHP 5: 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 (PDO) 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
under development. Late static binding had been missing
from PHP and was added in version 5.3. 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. Over time, PHP interpreters became available
on most existing 32-bit and 64-bit operating systems, either by building
them from the PHP source code, or by using pre-built
binaries. For the PHP versions 5.3 and 5.4, the only available Microsoft Windows
binary distributions were 32-bit x86 builds, requiring Windows 32-bit
compatibility mode while using Internet Information Services (IIS) on a 64-bit
Windows platform. PHP version 5.5 made the 64-bit x86-64
builds available for Microsoft Windows. PHP 6 and Unicode: PHP has received
criticism due to lacking native Unicode support at the core language level,
instead only supporting byte strings. In 2005, a project headed by Andrei Zmievski
was initiated to bring native Unicode support throughout PHP, by embedding the
International Components for Unicode (ICU) library, and representing text
strings as UTF-16 internally. Since this would cause major changes both to the
internals of the language and to user code, it was planned to release this as
version 6.0 of the language, along with other major features then in development.
However, a shortage of developers who understood the necessary changes, and
performance problems arising from conversion to and from UTF-16, which is
rarely used in a web context, led to delays in the project. As a result,
a PHP 5.3 release was created in 2009, with many non-Unicode features back-ported
from PHP 6, notably namespaces. In March 2010, the project in its current
form was officially abandoned, and a PHP 5.4 release was prepared containing most
remaining non-Unicode features from PHP 6, such as traits and closure re-binding.
Initial hopes were that a new plan would be formed for Unicode integration, but as
of 2014 none had been adopted. PHP 7: During 2014 and 2015, a new major
PHP version was developed, which was numbered PHP 7. The numbering of
this version involved some debate. While the PHP 6 Unicode experiment had never been
released, several articles and book titles referenced the PHP 6 name, which
might have caused confusion if a new release were to reuse the name. After a
vote, the name PHP 7 was chosen. The foundation of PHP 7 is
a PHP branch that was originally dubbed PHP next generation (phpng).
It was authored by Dmitry Stogov, Xinchen Hui and Nikita Popov, and aimed to
optimize PHP performance by refactoring the Zend Engine to use more compact data
structures with improved cache locality while retaining near-complete language
compatibility. As of 14 July 2014, WordPress-based benchmarks, which served
as the main benchmark suite for the phpng project, showed an almost 100%
increase in performance. Changes from phpng are also expected to make it easier
to improve performance in the future, as more compact data structures and other
changes are seen as better suited for a successful migration to a
just-in-time (JIT) compiler. Because of the significant changes, the reworked Zend Engine
is called Zend Engine 3, succeeding Zend Engine 2 used in PHP
5. Because of major internal changes in phpng, it must receive a new major
version number of PHP, rather than a minor PHP 5 release, according to
PHP's release process. Major versions of PHP are allowed to break backward-
compatibility of code and therefore PHP 7 presented an opportunity for other
improvements beyond phpng that require backward-compatibility breaks, including
wider use of exceptions, reworking variable syntax to be more consistent
and complete, and the deprecation or removal of various legacy features. PHP 7
also introduced new language features, including return type
declarations for functions, which complement the existing parameter type declarations, and
support for the scalar types (integer, float, string, and boolean) in parameter
and return type declarations. Beginning on June 28, 2011, the PHP Group
implemented a timeline for the release of new versions of PHP. Under this system,
at least one release should occur every month. Once per year, a minor release
should occur which may include new features. Every minor release should at
least be supported for two years with security and bug fixes, followed by at
least one year of only security fixes, for a total of a three-year release
process for every minor release. No new features,
unless small and self-contained, are to be introduced into a minor release
during the three-year release process. Thank you, A.I. I hope you found this video
educational about PHP. Please, hit that like button. If you haven't subscribed,
please subscribe. And, catch you later.
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