**[ChooseALicense.com](https://choosealicense.com)** aims to provide **accurate**, **non-judgmental**, and **understandable** information about popular **open source licenses** in order to **help people make informed decisions** about the projects they start, maintain, contribute to, and use.
We catalog [select](CONTRIBUTING.md#adding-a-license) open source licenses with a [Jekyll collection](https://jekyllrb.com/docs/collections/) (in `_licenses`). The catalog is used to render [ChooseALicense.com](https://choosealicense.com) and is regularly vendored into [Licensee](https://github.com/licensee/licensee), which GitHub uses to provide a [license chooser and license detection](https://help.github.com/articles/adding-a-license-to-a-repository/), a [licenses API](https://developer.github.com/v3/licenses/), and to [display license descriptions and metadata](https://github.com/blog/2335-open-source-license-descriptions-and-metadata).
* Be accurate, non-judgmental, and understandable. Our goal is to help you find a license that meets *your* goals.
* The homepage should have just enough to help most folks make a decision about what license to use for a project they contribute to.
* For the rest, the site will contain additional information about licenses common to specific communities and situations.
* Collaborate with and reinforce other licensing best practices and standards projects.
* 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.
If you encounter any issues with the above steps, please refer to the official [Jekyll](https://jekyllrb.com/docs/) documentation and this [guide on running Jekyll as a non-superuser](https://jekyllrb.com/docs/troubleshooting/#no-sudo) for more detailed installation instructions.
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:
*`using` - A map of 3 notable projects using the license with straightforward LICENSE files which serve as examples newcomers can follow and that can be detected by [licensee](https://github.com/licensee/licensee) in the form of `project_name: license_file_url`
*`hidden` - Whether the license is neither [popular](https://opensource.org/licenses) nor fills out the [spectrum of licenses](https://choosealicense.com/licenses/) from strongly conditional to unconditional (defaults to true)
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
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.
*`include-copyright--source` - A copy of the license and copyright notice must be included with the software in source form, but is not required for binaries.
*`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.
*`same-license--file` - Modifications of existing files must be released under the same license when distributing the software. In some cases a similar or related license may be used.
*`same-license--library` - Modifications must be released under the same license when distributing the software. In some cases a similar or related license may be used, or this condition may not apply to works that use the software as a library.
*`trademark-use` - This license explicitly states that it does NOT grant trademark rights, even though licenses without such a statement probably do not grant any implicit trademark rights.
The content of this project itself is licensed under the [Creative Commons Attribution 3.0 Unported license](https://creativecommons.org/licenses/by/3.0/), and the underlying source code used to format and display that content is licensed under the [MIT license](LICENSE.md).