First of all, we have inheritance, which shows the IS-A relationship between classes.

class FlyingEnemy: public Enemy 
{ 
  public: 
    void Fly(void); 
  private: 
    int flySpeed; 
};

When an object inherits from another object, it has all of the methods and fields that are contained in the parent class, while also adding their own content and features. In this instance, we have a special FlyingEnemy, which has the ability to fly in addition to all of the functionality of the Enemy class.

In UML, this is normally shown by a solid line with a hollow arrow and looks like the following: