What is the advantage of using polymorphism in object-oriented programming design?

Polymorphism allows objects of different classes to be processed through a single interface, which simplifies the extensibility and maintenance of code. Thanks to polymorphism, it is possible to write more flexible and scalable programs, where new object types can be added without modifying existing code, by overriding methods.

Example in Python:

class Animal:
    def speak(self):
        pass

class Dog(Animal):
    def speak(self):
        return "Woof"

class Cat(Animal):
    def speak(self):
        return "Meow"

animals = [Dog(), Cat()]
for animal in animals:
    print(animal.speak())  # Calls the appropriate method for each object

This allows working with different objects uniformly, without worrying about specific classes.