All accounts come populated with two “automatic” groups: All Members and Public. These are useful for providing a general access to material.
Use the All Member Group to give everyone in your Mediagraph organization access to certain assets.
Use the Public Group to make assets accessible to anyone who finds your Mediagraph account.
While there is not an option to delete these Groups or control membership, you can edit their settings just like any other Group in Mediagraph:
Notice there is no option to delete Public or All Members Groups.