The ''PHP License'' is the

software license A software license is a legal instrument (usually by way of contract law, with or without printed material) governing the use or redistribution of software. Under United States copyright law, all software is copyright protected, in both source ...

under which the

PHP PHP is a general-purpose scripting language geared toward web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementation is now produced by The PHP Group ...

scripting language is released. The PHP License is designed to encourage widespread adoption of the source code. Redistribution is permitted in

source Source may refer to: Research * Historical document * Historical source * Source (intelligence) or sub source, typically a confidential provider of non open-source intelligence * Source (journalism), a person, publication, publishing institute o ...

binary Binary may refer to: Science and technology Mathematics * Binary number, a representation of numbers using only two digits (0 and 1) * Binary function, a function that takes two arguments * Binary operation, a mathematical operation that t ...

form with or without modifications, with some caveats. Version 3 of PHP used a

dual license Multi-licensing is the practice of distributing software under two or more different sets of terms and conditions. This may mean multiple different software licenses or sets of licenses. Prefixes may be used to indicate the number of licenses ...

—PHP 3's source is available under either the PHP License or the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the Four Freedoms (Free software), four freedoms to run, study, share, and modify the software. The license was th ...

(GPL). This practice was discontinued as of PHP 4, with PHP's developers citing the restrictions on reuse associated with the GPL's

copyleft Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose, ...

enforcement as being the reason for dropping it. The

Zend Engine The Zend Engine is a compiler and runtime environment for the PHP scripting language and consists of the Zend Virtual Machine, which is composed of the Zend Compiler and the Zend Executor, that compiles and executes the PHP code. It was origin ...

, the core of the PHP interpreter, is separately licensed under the similar Zend Engine License, which contains similar naming restrictions to the PHP license (applying to the names "Zend" and "Zend Engine"), and a clause requiring advertising materials to mention its use.

Criticism

The PHP License is an

open source license An open-source license is a type of license for computer software and other products that allows the source code, blueprint or design to be used, modified and/or shared under defined terms and conditions. This allows end users and commercial compa ...

according to the

Open Source Initiative The Open Source Initiative (OSI) is the steward of the Open Source Definition, the set of rules that define open source software. It is a California public-benefit nonprofit corporation,_with_501(c)(3).html" ;"title="110. - 6910./ref> is a type o ...

, and a non-

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...

license according to the

Free Software Foundation The Free Software Foundation (FSF) is a 501(c)#501(c)(3), 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985, to support the free software movement, with the organization's preference for software being distributed ...

. The license is GPL-incompatible due to restrictions on the usage of the term ''PHP''.

Debian Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of D ...

maintainers have had a long-standing discussion (since at least 2005) about the validity of the PHP license. Expressed concerns include that the license "contains statements about the software it covers that are specific to distributing PHP itself", which, for other software than PHP itself therefore would be "false statements". Debian has a specific policy for the license (and requires a statement in debian/copyright file when it is used): "The PHP license must only be used for PHP and PHP add-ons."

References

External links

Official PHP License Information

Zend Grant Documents
{{DEFAULTSORT:Php License Free and open-source software licenses PHP

Criticism

See also

References

External links