| This declares a class Point and defines an object apoint. You can think of a class definition as a structure definition with functions (or ``methods''). Additionally, you
| can specify the access rights in more detail. For example, _x and _y are private, because elements of classes are private as default. Consequently, we explicitly
| must ``switch'' the access rights to declare the following to be public. We do that by using the keyword public followed by a colon: Every element following this
| keyword are now accessible from outside of the class.
| Recall that a structure struct is a combination of various data elements which are accessible from the outside. We are now able to express a structure with help of
| a class, where all elements are declared to be public.
| This is exactly what C++ does with struct. Structures are handled like classes. Whereas elements of classes (defined with class) are private by default, elements
| of structures (defined with struct) are public. However, we can also use private: to switch to a private section in structures.