The attributes inside animal class are declared as private, encapsulating the internal state of the class. They could be controlled by setter and gester, providing a level of abstraction and protection for the internal data.
Animal class is declared as abstract class which means by extended by subclasses. Example of makesound() which provide their own implementation for making a sound.
In the Dog class it inherits the attributes and methods defined in 'Animal class' and also provide its own specific implementations.
The speak() method in the AnimalClass is overridden in the Dog class. When an object of type Dog is used, the overridden speak() method in the Dog class is invoked