The zlib license is a
permissive free software license
A permissive software license, sometimes also called BSD-like or BSD-style license, is a free-software license which instead of copyleft protections, carries only minimal restrictions on how the software can be used, modified, and redistributed, ...
which defines the terms under which the
zlib software library
In computer science, a library is a collection of non-volatile resources used by computer programs, often for software development. These may include configuration data, documentation, help data, message templates, pre-written code and sub ...
can be distributed. It is also used by many other
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, n ...
packages. The
libpng
libpng is the official Portable Network Graphics (PNG) reference library (originally called pnglib). It is a platform-independent library that contains C functions for handling PNG images. It supports almost all of PNG's features, is extensib ...
library uses a similar license sometimes referred interchangeably as zlib/libpng license.
The zlib license has been approved by the
Free Software Foundation
The Free Software Foundation (FSF) is a 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 under copyleft ( ...
(FSF) as a
free software license
A free-software license is a notice that grants the recipient of a piece of software extensive rights to modify and redistribute that software. These actions are usually prohibited by copyright law, but the rights-holder (usually the author) ...
,
and by 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) tax-exempt status.
The organization wa ...
(OSI) as 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 comp ...
.
It is
compatible with 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 to run, study, share, and modify the software. The license was the first copyleft for general ...
.
Terms
The license only has the following points to be accounted for:
* Software is used on 'as-is' basis. Authors are not liable for any damages arising from its use.
* The distribution of a modified version of the software is subject to the following restrictions:
*# The authorship of the original software must not be misrepresented,
*# Altered source versions must not be misrepresented as being the original software, and
*# The license notice must not be removed from source distributions.
The license does not require
source code
In computing, source code, or simply code, is any collection of code, with or without comments, written using a human-readable programming language, usually as plain text. The source code of a program is specially designed to facilitate the ...
to be made available if distributing binary code.
Text
The license terms are as follows:
See also
*
Authentication Open-Source License
*
Software using the Provider license (category)
References
External links
License text on the zlib homepage
Free and open-source software licenses
Permissive software licenses
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