PHP1

In 1994, a brother named Rasmus Lerdorf developed a script in Perl in order to display his resume and web traffic statistics on the Internet. Later, due to the growing demand, Lerdorf rewrote the program in C language. The rewritten program supported database access. And simple development of a Web application, which was well received, and the first version was released under the name Personal Home Page Tools.

PHP2

In order to improve PHP and develop it quickly, Lerdorf opened it open source on June 8, 1995, and thus PHP2.0 came out and was named PHP/FI. After several beta releases, the official version was released in 1997. At this point, PHP is installed on 50,000 domain names worldwide, or 1% of all domain names.

PHP3

Before the official PHP/FI release, Zeev Suraski and Andi Gutmans, two Israeli engineers, had already started rewriting the PHP parser to lay the foundation for PHP3.0, so after the release of PHP/FI, they opened up testing of PHP3.0. It was officially released in June 1998. At this point PHP was officially renamed PHP:Hypertext Preprocessor.

In addition to providing users with an infrastructure of databases, protocols, and apis, PHP3.0 is highly extensible and has attracted a large number of developers to join and submit new modules, which is also the key to PHP3.0’s great success.

PHP4

After the official release of PHP3.0, Zeev Suraski and Andi Gutmans began rewriting the PHP kernel, naming it the Zend Engine (short for Zeev and Andi), also known as the Zend Engine. The engine was introduced to PHP4.0 in 1999 and was officially released in 2000. PHP4.0 not only has better performance, but also supports sessions, output buffering, and other features, attracting a large number of developers. At this point, the number of sites that install PHP has reached millions, accounting for 20% of all sites.

PHP5

On July 13, 2004, PHP5 based on Zend Engine 2.0 was released, fully introducing object-oriented mechanisms and preserving backward compatibility. Subsequent releases of versions 5.3 through 5.6 added namespaces, closures, Traits, and short arrays to make PHP syntax more flexible, and PHP5.6 is still widely used today.

PHP6

We all know that PHP doesn’t release 6.0, the reason is that there was a group of people to create a v6 project, the main purpose is to increase Unicode support for the PHP engine, the developers at the same time maintain the development of 5 and 6, slowly everyone waiting to discover new functions to 6, and 6 because of the slow development lead to a lot of new features can not submit, The condition was not ideal, and then 6 was not developed. After a final vote by the PHP community’s core contributors, more than 70% agreed that the latest version of PHP would be PHP7, not PHP6, so PHP skipped version 6.0.

PHP7

In 2014, when PHP7 was officially released, the Zend Engine was rewritten as Zend Engine 3.0, which greatly improved the performance of the PHP language. Numerous tests showed that PHP7 had 60% to 200% performance improvement over PHP5.6 in various open source projects.

It is worth mentioning here that “Hui Xinchen”, the core developer of PHP7 and the main developer of PHP5.4 and PHP5.5, is a core member of the PHP development team and the most influential PHP technical expert in China, nicknamed “Brother Bird”.