>> This page on the wikiSo you made a mod. Excellent, but even though you may think you are done, you still have one final step before you can distribute it to everyone: you must choose how it will be licensed. Licensing affects how others will be able to use your mod. Too strict and your mod becomes isolated and usable only for playing, too loose and you may find parts of your mod used in ways that you don't want.
For clarification, it's not your mod you are licensing, it's every individual file in that mod. Thus, when you say your mod is licensed under CC-BY-SA, this means every individual file is CC-BY-SA. You can have multiple licenses by making some files one license and some others. For example, the music might be CC-BY-SA, while the rest could be the laxer CC-BY. This is generally done by having a plain text filed named "AUTHORS", etc distributed with your mod explaining what files are under what licenses.
We are going to assume that you wish to have your mod available for free, and that others will be able to use your resources. Glest itself follows these principles, so sharing is the norm around here, and will likely increase the success and popularity of your mod. For this purpose, there are the following main licenses:
CC-BYCreative Commons Attribution is a license that permits other people to use your work in virtually any way they want, as long as they give you proper credit. This can include your name (e.g. Ringo Starr), your pseudonym (e.g. BeatleDrums420), and/or a link to your website (e.g.
http://beatledrums420.example.org).
Why you might want to use this license: You want everyone to be able to use your work in their own projects, for whatever purpose and whatever kind of project they want, but you want credit to be given where credit is due. If that sounds like you, this is your license. This license is also compatible with nearly every license under the sun (including the GPL), so the content is highly reusable. Also, if the developers of another game use your content, you can always put that on your résumé.
Why you might NOT want to use this license: If you want to pick and choose how people use, modify, or redistribute your work, this is not the license for you.
CC-BY-SACreative Commons Attribution Share-alike and Non-commercial share-alike are similar. People can share (copy, distribute and transmit) the work, and remix (adapt) the work. It includes the same attribution terms as CC-By, so you can still include your name, pseudonym, and/or web address.
When someone shares or remixes the work, they must attribute the work in the manner specified by the author or licensor (in this case, you) (but not in any way that suggests that they endorse you or your use of the work). If they alter, transform, or build upon this work, they may distribute the resulting work only under the same or similar license to this one. This means that if you make something for a Glest mod and another modder, artist, or developer wants to use it in their own project, you get credit for it and it remains under CC-By-SA.
These limitations can be waived if they get permission from the copyright holder (you), and where the work or any of its elements is in the public domain under applicable law, that status is in no way affected by the license.
Why you might want to use this license: Others will be able to use your content in their own projects, and any modifications and/or improvements they make will also be shared back with the community and you (so it encourages even more sharing). This ensures that the content will be used only in projects with Free/Open content, such as Free and Open-Source games, and not in the next
Command & Conquer title.
Why you might NOT want to use this license: The downside to CC-By-SA is that it can ONLY be used with other CC-By-SA assets. This is why you may want to consider dual-licensing, or using CC-By instead.
http://creativecommons.org/licenses/by-sa/3.0/us/CC-BY-NC-SACreative Commons Attribution Share-alike and Non-commercial Share-alike have many similarities, but there is a key difference. Non-commercial (NC) content cannot be used in commercial projects.
Why you might want to use this license: You want your work to be distributed for personal/private use, or you yourself want to make money from it while keeping others from competing with you.
Why you might NOT want to use this license: Work under this license is incompatible with most other free licenses (including CC-By-SA and GPL), which makes it tricky to incorporate this work in other projects. Thus, this content is most suited to personal use by players, not distribution in another project.
http://creativecommons.org/licenses/by-nc-sa/3.0/us/GPLThe GPL, or GNU General Public License is a free license that gives the ability to let others modify your work, and is the most commonly used free license. The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it. To protect your rights, the GPL needs to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.
For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights. For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.
The GPL is not really meant for content, but rather for programs. However, some Free and Open-Source projects use GPL for art assets anyway. Neither the GPL nor any of the CC licenses are exclusive, so in fact you can license a work as
both GPL and CC-something (and/or numerous other licenses), allowing the user to use the content under whichever terms are more favorable. For example, dual-licensing a work as CC-By-SA
and GPL allows games with CC-By-SA art (like 0AD) and ones with GPL art (like The Battle for Wesnoth) to both use your content, but still keeps it out of the hands of those who are themselves unwilling to share.
Why you might want to use this license: If you want to allow other games with GPL art to use your content, this is a good choice. However, it is preferable that you
also release it under one of the CC licenses as well, to ensure greater compatibility/reusability.
Why you might NOT want to use this license: If you license your content only as GPL, then it will only be usable in other GPL projects, not in anything else. Dual-licensing gets around this.
http://www.gnu.org/licenses/gpl.htmlCC0 (Public Domain)If you don't want to have any restrictions at all, and don't mind if others can use your work in any way (which can include uncredited usage in commercial applications), then CC0 (zero) is basically a public domain license.
In contrast to CC’s licenses that allow copyright holders to choose from a range of permissions while retaining their copyright, CC0 empowers yet another choice altogether – the choice to opt out of copyright and database protection, and the exclusive rights automatically granted to creators – the “no rights reserved†alternative to our licenses.
Why you might want to use this license: You want everyone to be able to use your work however they please, and you don't really care whether you get credit or not. Alternatively, if the work is small or not very significant (like a single sound effect), and you don't want other modders, artists, or developers to have to bother crediting you, CC0 can save them the trouble.
Why you might NOT want to use this license: If someone uses your CC0-licensed work in a way that you don't like, there is not much you can do about it. Also, if anyone else's work is included in your work, you MUST have permission from the other author(s) in order to release it into the public domain. This means that if you're using any content from Glest's original assets (e.g. Magitech), you cannot use this license for that work because it doesn't entirely belong to you. You can, however, use multiple licenses, with the copyrighted assets under their respective licenses and only what you made under CC0.
http://creativecommons.org/about/cc0Helpful LinksRecommendationPersonally, I recommend using CC-BY-SA, as it is the most versatile and allows people to modify your assets while still protecting them better than the GPL. The non-commercial variant is not recommended because it can prevent some modders from using your media. The GPL is not meant for assets, so does not cover them as well. CC-BY-SA is also one of the most commonly used free licenses in the world, being used on many large projects like Wikipedia, Wikia, and many Glest mods.
This main post may be frequently updated. Moderators may edit as they see fit, but should leave an edit summary below.
Edit History:
11/05/2011 3:57am GMT - Omega: First version of this page
11/05/2011 4:05am GMT - Omega: Expanded CC0 section
11/05/2011 4:14am GMT - Omega: Added wiki link
11/05/2011 4:24am GMT - Omega: New "Helpful Links" section
11/05/2011 5:13am GMT - Omega: Added a recommendation
11/05/2011 6:11am GMT - Ultifd: Added link to license chooser at top
11/05/2011 6:53am GMT - Omega: Modified sentence structure of previously added line
11/05/2011 6:06pm GMT - Omega: Change as per John: https://forum.megaglest.org/index.php?topic=7106.msg72897#msg72897
14/05/2011 3:27am GMT - Omega: Clarification on how multiple licenses work, also, sticked by John.d.h
