GitHub is a popular repository for developers and users to leave copies of code and information that can be shared with others in an Open Source manner.
However as a recent article highlights (1 in 600 Top Websites Dangerously Exposed) some of the data stored in GitHub without any security enabled may expose a business to issues and security risks.
There are two types of repos available on GitHub*
Public repositories are a great choice for getting started! They’re visible to any user on GitHub, so you can benefit from a collaborative community.
Private repositories require a little more setup. They’re only available to you, the repository owner, as well as any collaborators you choose to share with. Private repositories are only available for paid accounts.
It is possible to create a Private Repo for several users. This is not a free option, but is however available at a reasonable cost https://github.com/pricing
You can also implement 2FA for your account for additional security – 2FA Documentation