Open-source license

An open-source license is a copyright License for computer software that makes the source code available under terms that allow for modification and redistribution without having to pay the original author. Such licenses may have additional restrictions such as a requirement to preserve the name of the authors and the copyright statement within the code. One popular (and sometimes considered normative) set of open source licenses are those approved by the Open Source Initiative (OSI) based on their Open Source Definition (OSD).

=Comparisons=

There are also shared source licenses which have some similarities with open source, but a number of critical differences make such licenses incompatible with the Open Source Definition.

Some software licenses define an open standard basis and may or may not be similar to open source, like some versions of Solaris Operating Environment and PGP.

The Free Software Foundation has related but distinct criteria for evaluating whether or not a license qualifies a program as free software. See Free software license and Open source vs. free software.

Likewise, the Debian project has its own criteria, the Debian Free Software Guidelines, which in many ways was a precursor to the Open Source Definition.

=OSI approved licenses=

: *Academic Free License *Adaptive Public License (APL) *Apache Software License *Apple Public Source License *Artistic License *Attribution Assurance Licenses *BSD License *Computer Associates Trusted Open Source License *Common Development and Distribution License *Common Public License *End-User License Agreement (EULA) *EU DataGrid Software License *Eclipse Public License *Educational Community License *Eiffel Forum License *Entessa Public License *Fair License *Frameworx License *GNU General Public License (GPL) *GNU Lesser General Public License (LGPL) *Historical Permission Notice and Disclaimer *IBM Public License *Intel Open Source License *Jabber Open Source License *Lucent Public License *MIT License *MITRE Collaborative Virtual Workspace License (CVW License) *Motosoto License *Mozilla Public License 1.0 (MPL) *Mozilla Public License 1.1 (MPL 1.1) *NASA Open Source Agreement *Naumen Public License *NetHack General Public License *Nokia Open Source License *OCLC Research Public License *Open Group Test Suite License *Open Software License *PHP License *Python programming language License *Python programming language Software Foundation License *Qt Public License (QPL) *RealNetworks Public Source License *Reciprocal Public License *Ricoh Source Code Public License *Sleepycat License *Sun Microsystems/SISSL (SISSL) *Sun Public License (SPL) *Sybase Open Watcom Public License *University of Illinois/NCSA Open Source License *Vovida Software License v. 1.0 *W3C License *wxWindows Library License *X.Net License *zlib-libpng license *Zope Public License

=Non-OSI source licenses=

Licenses which are source-available but not OSI-Certified include: *Hacktivismo Enhanced-Source Software License Agreement *Solaris Operating Environment *PGP

=See also=

*Free Software Foundation *Open source movement *Software license

=External links=

*[http://www.opensource.org/ The Open Source Initiative]

*[http://books.slashdot.org/article.plsid=04/09/21/0239245 Open Source Licensing] — a review and discussion of Lawrence Rosen s book Open Source Licensing: Software Freedom and Intellectual Property Law (ISBN 0131487876) on slashdot *[http://pgl.yoyo.org/lqr/ Open Source License Quick Reference Chart] — a chart comparing various aspects of Open Source licenses, with the option to select your bias. Based on Zooko s document, [http://zooko.com/license_quick_ref.html Open Source Reference for Choosing a Free Software License].