Organizations at GitHub are a layer on top of Git. They can be seen as a way to provide access control to associated repositories.
When GitHub users explore the repositories associated with your organizations, they will be subject to the privileges you have set up. This means that you are in charge of what you allow others to see.
If you are a paying customer at GitHub, your organization can have private repositories. A private repository is only accessible by members of the organization. A company can have open source projects or examples as public repositories. But, by using a private repository, it is possible to have some company secrets.
