A lot of repositories on GitHub.com don't have a license. GitHub provides a license chooser, but if you don't know anything about licenses, how are you supposed to make an informed decision?
[ChooseALicense.com](http://www.choosealicense.com "Choose A Licence website") is designed to help people make an informed decision about licenses by demystifying license choices through non-judgmental guidance.
* For the 1%, the site will contain a list of licenses common to specific communities and situations.
* Not comprehensive. Seems like an odd goal, but there are a bajillion licenses out there. We're going to have to filter that down to a small list of those that matter.
For information on adding a license, see [the CONTRIBUTING file](https://github.com/github/choosealicense.com/blob/gh-pages/CONTRIBUTING.md#adding-a-license).
Licenses sit in the `/_licenses` folder. Each license has YAML front matter describing the license's properties. The body of the file contains the text of the license in plain text. The available metadata fields are:
*`tab-slug` - If part of a license family, a license slug containing only `a-z`, `0-9`, and `_` characters, used for internal links on the licenses page
The licenses on choosealicense.com are regularly imported to GitHub.com to be used as the list of licenses available when creating a repository. When we create a repository, we will replace certain strings in the license with variables from the repository. These can be used to create accurate copyright notices. The available variables are:
#### Fields
*`fullname` - The full name or username of the repository owner
*`login` - The repository owner's username
*`email` - The repository owner's primary email address
*`project` - The repository name
*`description` - The description of the repository
*`year` - The current year
## License properties
The license properties (rules) are stored as a bulleted list within the licenses YAML front matter. Each rule has a name e.g., `include-copyright`, a human-readable label, e.g., `Copyright inclusion`, and a description `Include the original copyright with the code`. To add a new rule, simply add it to `_data/rules.yml` and reference it in the appropriate license.
### Rules
#### Required
*`include-copyright` - Include a copy of the license and copyright notice with the code.
*`document-changes` - Indicate significant changes made to the code.
*`same-license` - Modifications must be released under the same license when distributing the software. In some cases a similar or related license may be used.
*`trademark-use` - While this may be implicitly true of all licenses, this license explicitly states that it does NOT grant you any rights in the trademarks or other marks of contributors.
*`no-liability` - Software is provided without warranty and the software author/license owner cannot be held liable for damages.
*`modifications` - This software may not be modified.
*`distribution` - You may not distribute this software.
## License
The content of this project itself is licensed under the [Creative Commons Attribution 3.0 license](http://creativecommons.org/licenses/by/3.0/us/deed.en_US), and the underlying source code used to format and display that content is licensed under the [MIT license](http://opensource.org/licenses/mit-license.php).