Many developers have the misconception that “if a project is on GitHub or GitLab, it’s open source.” However, without a license, the source code is, by default, subject to copyright and not open source. Even if a project has a LICENSE file, it could still be an imposter if it doesn’t provide the rights outlined in the open source definition. This is why open source has established an umpire for open source licenses.

If you don’t know the difference between “open source” software and “source available” software, it’s time to fix that.