The ''PHP License'' is the
software license under which the
PHP
PHP is a General-purpose programming language, 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 implementati ...
scripting language is released. The PHP License is designed to encourage widespread adoption of the source code. Redistribution is permitted in
source or
binary form with or without modifications, with some caveats.
Version 3 of PHP used a
dual license—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 user
In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ulti ...
(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 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 according to the
Open Source Initiative, and a non-
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, ...
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, ...
license according to the
Free Software Foundation.
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 De ...
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."
See also
*
Apache License
*
Software using the PHP license (category)
References
External links
Official PHP License InformationZend Grant Documents
{{DEFAULTSORT:Php License
Free and open-source software licenses
PHP