A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.
For questions about the Creative Commons "CC0" public domain dedication that allows copyright holders to place works in the public domain to the extent legally possible, worldwide
For questions about Eclipse Public License (EPL), that is a certified Open Source license created specifically for the Eclipse Foundation.
For questions about the Open Source Initiative and its relationship to free and open projects.
Code which has not been published under a license and can be used only under regular copyright law.
For questions about non-legalese licenses written by programmers either jokingly or to be understandable.
For questions about the Creative Commons CC-BY-NC (Attribution-NonCommercial) license
The Free Software Foundation defined the term Free Software and is owner of the GNU-licenses.
.For questions concerning the promotion and advertising of open projects, and their implications with the general public, society, and respective organizations.
For questions that deals with freedoms normally provided and/or guaranteed by Free and Open Software.
Questions about the history of open projects, philosophies, and coming to being.
For questions about statistical data relevant to the FLOSS movement
Questions about GNU Free Documentation License (GFDL is copylefted)
For questions about permissive licenses, such as Apache or MIT. Note: this does not include public domain or CC0. Use [public-domain] instead.
For questions about the Common Development and Distribution License (CDDL)
Questions about the SIL Open Font License
For questions about the restrictive Creative Commons license, CC-BY-NC-ND meaning: no derivatives, commercial usages and mandatory attribution.