The leftmost column lists possible access rights for elements of classes. It also includes a third type protected. This type is used for elements which should be
directly usable in subclasses but which should not be accessible from the outside. Thus, one could say elements of this type are between private and public
elements in that they can be used within the class hierarchy rooted by the corresponding class.
The second and third column show the resulting access right of the elements of a superclass when the subclass is privately and publically derived, respectively.