Free license
A free license or open license is a license which allows others to reuse another creator’s work as they wish. Without a special license, these uses are normally prohibited by copyright, patent or commercial license. Most free licenses are worldwide, royalty-free, non-exclusive, and perpetual (see copyright durations). Free licenses are often the basis of crowdsourcing and crowdfunding projects. The invention of the term "free license" and the focus on the rights of users were connected to the sharing traditions of the hacker culture of the 1970s public domain software ecosystem, the social and political free software movement (since 1980) and the open source movement (since the 1990s). These rights were codified by different groups and organizations for different domains in Free Software Definition, Open Source Definition, Debian Free Software Guidelines, Definition of Free Cultural Works and The Open Definition. These definitions were then transformed into licenses, using the copyright as legal mechanism. Ideas of free/open licenses have since spread into different spheres of society. Open source, free culture (unified as free and open-source movement), anticopyright, Wikimedia Foundation projects, public domain advocacy groups and pirate parties are connected with free and open licenses. Public domain licenses Creative Commons CC0 WTFPL Unlicense Public Domain Dedication and License (PDDL) Permissive licenses Apache License BSD License MIT License Mozilla Public License (file-based permissive copyleft) Creative Commons Attribution Copyleft & patentleft licenses GNU GPL, LGPL (weaker copyleft), AGPL (stronger copyleft) Creative Commons Attribution Share-Alike Mozilla Public License Common Development and Distribution License GFDL (without invariant sections) Free Art License Open-source software The Open Source Definition Open Content Open Content License Open Publication License Open-source hardware Open database Creative Commons v4 Open Database Licence Creative Commons Free Software Foundation Open Source In