Php/fi
PHP inherits from an old project called Php/fi. Php/fi was created in 1995 by Rasmus Lerdorf, initially a simple Perl script that tracks the information of people accessing his page. It named this set of scripts "Personal Home Page Tools". As more functional requirements increase, Rasmus writes a larger C language implementation, which can access the database, allowing users to develop simple dynamic WEB programs. Rasmus» released the source code for PHP/FI so everyone can use it, and you can fix it and improve its source code.
PHP/FI, a program that provides an interpreter for your home page/form, already contains some of the basic features of PHP today. It has Perl-style variables, automatically interprets form variables, and can embed HTML. The syntax itself is very similar to Perl, but it is very limited, simple, and somewhat uncoordinated.
By 1997, Php/fi 2.0, the second edition of its C language, had thousands of users (estimates) and about 50,000 domain names installed around the world, about 1% of all domain names on the Internet. But then only a few people were writing a small amount of code for the project, and it was still just a human project.
The official version of PHP/FI 2.0 was released in November 1997 after a number of beta releases. Shortly after the release of the first alpha version of PHP 3.0, PHP became successful.
PHP 3
PHP 3.0 is the first version similar to today's PHP syntax structure. Andi Gutmans and Zeev Suraski, when developing e-commerce programs for a university project, found the PHP/FI 2.0 feature was significantly inadequate, and they rewritten the code. This is PHP 3.0. After Andi,rasmus and Zeev a series of efforts, taking into account the Php/fi existing user base, they decided to jointly release PHP 3.0 as the official successor of PHP/FI 2.0. The further development of the PHP/FI 2.0 terminated however nearly.
One of the most powerful features of PHP 3.0 is its extensibility. In addition to providing the infrastructure for the end user with databases, protocols, and APIs, its extensibility also attracts a large number of developers to join and submit new modules. It was later confirmed that this was the key to the great success of PHP 3.0. Other key features in PHP 3.0 include object-oriented support and a more powerful and coordinated syntax structure.
This new language accompanies a new name release. It removes from the name of PHP/FI 2.0 the section that implies "this language is limited to personal use". It is named the simple abbreviation "PHP". This is a recursive abbreviation, its full name is ――php:hypertext preprocessor.
By the end of 1998, PHP had installed nearly 10,000 people, with about 100,000 websites reporting that they were using PHP. At the top of PHP 3.0, it was installed on 10% of the Web servers on the Internet.
After about nine months of public testing, the official release of PHP 3.0 was officially launched in June 1998.
PHP 4
In the winter of 1998, shortly after PHP 3.0 was officially released, Andi Gutmans and Zeev Suraski began rewriting PHP code. The design goal is to enhance the performance of the complex program runtime and the modularity of PHP's own code. The new features of PHP 3.0 and the support of a wide range of third-party databases and APIs make it possible to write such programs, but PHP 3.0 does not have the ability to handle such complex programs efficiently.
The new engine, known as the "Zend engine" (the abbreviation for Zeev and Andi), succeeded in achieving the design goals and introduced PHP for the first time in mid-1999. PHP 4.0, which was based on the engine and combined with more new features, was released in May 2000, two years after the release of PHP 3.0. In addition to higher performance, PHP 4.0 includes other key features such as support for more Web servers, HTTP Sessions support, output buffering, more secure methods for handling user input, and some new language constructs.
Today, 10,000 developers (estimates) and millions of Web sites report that PHP is installed, accounting for 20% of the entire Internet domain name.
PHP's development team has a lot of good developers, while there are a lot of good people in the development of PHP-related projects, such as PEAR and PHP documentation works.
PHP 5
PHP 5 released its official version in July 2004 after a long period of development and multiple pre-release versions. Its core is the Zend Engine 2 generation, introducing a new object model and a number of new features.