Python OOP Concepts – Class, Object, Inheritance & More

Introduction – Why Learn OOP in Python?

Python is both a procedural and object-oriented language. For large-scale or modular software development, Object-Oriented Programming (OOP) offers key benefits:

• Code reusability
• Better encapsulation
• Easy maintenance and scalability

Whether you’re building a game, a web app, or an automation tool—OOP gives structure to your code.

In this guide, you’ll learn:

• What Object-Oriented Programming is
• The 4 pillars: Class, Object, Inheritance, Polymorphism
• Real-world code examples
• Best practices and FAQs

What is Object-Oriented Programming?

Object-Oriented Programming (OOP) is a programming paradigm centered around objects, which are instances of classes.

In Python, everything is an object, making it a natural fit for OOP.

1. Class and Object

Defining a Class

class Car:
    def __init__(self, brand, speed):
        self.brand = brand
        self.speed = speed

    def drive(self):
        return f"{self.brand} is driving at {self.speed} km/h."

Creating an Object

my_car = Car("Tesla", 120)
print(my_car.drive())

Output:

Tesla is driving at 120 km/h.

A class is a blueprint; an object is an instance of the class.

2. Encapsulation – Hiding Internal Details

class BankAccount:
    def __init__(self, balance):
        self.__balance = balance  # private attribute

    def deposit(self, amount):
        self.__balance += amount

    def get_balance(self):
        return self.__balance

acc = BankAccount(1000)
acc.deposit(500)
print(acc.get_balance())  # 1500

Encapsulation protects internal states using private attributes (__var) and public methods.

👪 3. Inheritance – Reuse Parent Class Features

class Animal:
    def speak(self):
        return "Some sound"

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

d = Dog()
print(d.speak())  # Bark

Inheritance lets you create a child class that reuses and overrides parent functionality.

4. Polymorphism – One Interface, Many Forms

class Bird:
    def fly(self):
        return "Flies in the sky"

class Airplane:
    def fly(self):
        return "Flies with fuel"

def let_it_fly(entity):
    print(entity.fly())

let_it_fly(Bird())       # Flies in the sky
let_it_fly(Airplane())   # Flies with fuel

Polymorphism allows different classes to use the same method name but with different behavior.

Additional OOP Concepts in Python

Constructors (__init__())

Used to initialize object attributes.

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

Destructors (__del__())

Called when the object is destroyed.

def __del__(self):
    print("Object deleted")

Class Variables vs Instance Variables

class Test:
    class_var = "Shared"

    def __init__(self):
        self.instance_var = "Unique"

Class Methods and Static Methods

class Demo:
    @classmethod
    def class_method(cls):
        print("This is a class method.")

    @staticmethod
    def static_method():
        print("This is a static method.")

Best Practices for Python OOP

Summary – Recap & Next Steps

Object-Oriented Programming in Python provides a solid foundation for structured, reusable, and maintainable code. From encapsulation to polymorphism, Python supports all major OOP principles in a simple syntax.

Key Takeaways:

• Class is a blueprint; object is an instance.
• Use encapsulation to protect state.
• Use inheritance to extend functionality.
• Polymorphism makes code flexible.
• Python supports both procedural and OOP styles.

Real-World Relevance:
Used in game development, web frameworks (like Django), APIs, GUI tools, and enterprise-level systems.

FAQ – Python OOP Concepts

What is the difference between a class and an object?

A class is a template, and an object is a real-world instance of that template.

What is self in Python?

self refers to the instance of the class. It’s used to access instance variables and methods.

How is Python different from Java in OOP?

Python uses dynamic typing, supports multiple inheritance, and has more flexible object creation. Java is strictly statically typed and uses interfaces for multiple inheritance.

What is the difference between @staticmethod and @classmethod?

• @staticmethod: No access to class or instance.
• @classmethod: Has access to the class (cls), not instance (self).

Can I override methods in Python?

Yes. Child classes can override parent methods by redefining them.