Multiple Levels of Derived Classes
It is possible to use a derived class as a base class for another derived class. In other words, you can create as many levels of derived classes as you want. For example, you could create a general TransportationVehicle class in line with Figure 16.1 and, from this class, derive a SurfaceVehicle class. This again could be a base class for a Car class that finally could become the base class for our well-known SportsCar, FamilyCar, and RacingCar classes, as illustrated in Figure 16.9.