Why Virtual Function?
Is to have derived classes inherit a function interface as well as a default implementation. But its not mandatory to redefine in its derived class. A virtual function allows derived classes to replace the implementation provided by the base class (OR) A virtual function allows a base pointer to be used and yet the right derived class function to be called Why should be base class destructor be virtual If you destroy an object through a pointer or reference to a base class and the base class destructor is not virtual then the derived class destructor are not executed and the destruction might not be complete. If not it leads to memory leaks.
