By default, Snapshots are created as private. If you have read permission for the Create Public Snapshot module, you can also create public Snapshots. A private snapshot is only available for viewing by the owner of the Snapshot. A public Snapshot is available for viewing by all users.
If you have read permission in the Snapshot module, you can turn your own private Snapshots into public Snapshots. You can turn any public Snapshot that you created into a private Snapshot, even if you do not currently have read permission in the Create Public Snapshot module.
For information about setting security permissions in the Create Public Snapshot module, refer to Security.