Nikola is released under the MIT license, which is a free software license. Some components shipped along with Nikola, or required by it are released under other licenses.
If you are not familiar with free software licensing, here is a brief explanation (this is NOT legal advice): In general, you can do pretty much anything you want — including modifying Nikola, using and redistributing the original version or the your modified version. However, if you redistribute Nikola to someone else, either a modified version or the original version, the full copyright notice and license text must be included in your distribution. Nikola is provided “as is”, and the Nikola contributors are not liable for any damage caused by the software. Read the full license text (LICENSE.txt) for details.
Copyright © 2012–2017 Roberto Alsina and others.
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.