Inheritance: Building on Other Classes

Reusing a class

Inheritance lets a new class start with everything another class has, and then add or change things.

Think of it like this: Cars, bikes and buses are all vehicles. They share things (wheels, a speed), but each has its own extras.

class Animal:
    def __init__(self, name):
        self.name = name

    def speak(self):
        return "..."

    def introduce(self):
        print(f"I am {self.name} and I say {self.speak()}")

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

class Cow(Animal):
    def speak(self):
        return "Moo"

for pet in [Cat("Kitty"), Cow("Gauri")]:
    pet.introduce()

Output

I am Kitty and I say Meow
I am Gauri and I say Moo

• class Cat(Animal): means Cat inherits from Animal. Animal is the parent, Cat is the child.
• Cat didn't write __init__ or introduce – it got them from Animal.
• Cat writes its own speak. This is called overriding a method.

Adding to the parent's setup with super()

class Employee:
    def __init__(self, name, salary):
        self.name = name
        self.salary = salary

class Manager(Employee):
    def __init__(self, name, salary, team):
        super().__init__(name, salary)
        self.team = team

boss = Manager("Kabir", 90000, ["Asha", "Ravi"])
print(boss.name, "manages", len(boss.team), "people")

Output

Kabir manages 2 people

super().__init__(...) runs the parent's setup first, then the child adds its own attribute.

Tip: Don't worry if classes feel strange at first. Write a few small ones – a Pet, a Player, a Product – and they'll start to click.