🐍 Python Lesson: Understanding Classes and Objects with Real Examples

If you're new to Python, you might have seen code that does… well, nothing at first. You copy-paste the code, run it, and the terminal shows… blank.

Let me show you why that happens — and how to turn that code into something powerful.

🔹 The Mysterious Code That Shows Nothing

First, let’s look at this code:

class Dog:

def init(self, name, age):

self.name = name

self.age = age

Now run this code in VS Code or any Python IDE.

❓ What Do You See in the Terminal?

Nothing. That’s right.

This is because the code only defines a class, a kind of blueprint. It doesn’t actually do anything unless you create an object and use its data or functions.

Let’s fix that.

🔧 Add These Lines:

my_dog = Dog("Willi", 6)

print(f"My dog's name is {my_dog.name}.")

print(f"My dog is {my_dog.age} years old.")

✅ Terminal Output:

My dog's name is Willi.

My dog is 6 years old.

Nice! Now the program actually shows something.

🚀 Code Examples to Understand Classes

Let’s go deeper by comparing three examples.

📦 Code 1: Dog

class Dog:

def init(self, name, age):

self.name = name

self.age = age

def sit(self):

print(f"{self.name} is now sitting.")

def roll_over(self):

print(f"{self.name} rolled over!")

🤖 Code 2: Robot

class Robot:

def init(self, model):

self.model = model

def move_arm(self):

print(f"{self.model} is moving its arm.")

def speak(self):

print(f"{self.model} says: Hello, human.")

🚗 Code 3: Car

class Car:

def init(self, brand):

self.brand = brand

def drive(self):

print(f"{self.brand} car is now driving.")

def brake(self):

print(f"{self.brand} car is braking.")

💡 Observations:

Code	About	Functions
Code 1	Dog	sit(), roll_over()
Code 2	Robot	move_arm(), speak()
Code 3	Car	drive(), brake()

🛠 Modifying Code 3 (Car → Truck)

Let’s change Car to Truck, and update its features.

🚚 Truck Version:

class Truck:

def init(self, model):

self.model = model

def move_forward(self, speed):

print(f"{self.model} truck is moving forward at {speed} km/h.")

def move_backward(self, speed):

print(f"{self.model} truck is reversing at {speed} km/h.")

def turn_left(self, angle):

print(f"{self.model} truck is turning left by {angle} degrees.")

✅ Try This:

my_truck = Truck("Ford")

my_truck.move_forward(40)

my_truck.move_backward(20)

my_truck.turn_left(45)

Terminal Output:

Ford truck is moving forward at 40 km/h.

Ford truck is reversing at 20 km/h.

Ford truck is turning left by 45 degrees.

🧠 What’s Happening Here?

You’ve now learned:

How to define a class (blueprint).

How to create an object from it.

How to use methods (functions inside the class).

How to customize data using the init method.

🔄 Using Multiple Objects from One Class

You can reuse the same class to make multiple objects:

my_car = Car("Toyota")

your_car = Car("Honda")

my_car.drive()

your_car.brake()

Each object keeps its own data but shares the structure.

🆕 Let’s Build a New Program

Idea: Track the entry time of students coming to class.

We want to build a structure that stores each student’s name and their entry time.

👨‍🏫 Student Entry Tracker:

class StudentEntry:

def init(self, name, time):

self.name = name

self.time = time

def show_entry(self):

print(f"{self.name} entered the class at {self.time}.")

✅ Try This:

student1 = StudentEntry("Ravi", "9:00 AM")

student2 = StudentEntry("Sita", "9:05 AM")

student1.show_entry()

student2.show_entry()

Terminal Output:

Ravi entered the class at 9:00 AM.

Sita entered the class at 9:05 AM.

🎯 Final Thoughts

Classes help you organize data and behavior.

Objects created from classes are like custom tools you build yourself.

You can start with one example (dog, robot, car), then build your own programs using the same concept.

💬 What to Try Next?

Add more features to your truck or car (like honk(), load_cargo()).

Build a class for LibraryBook with methods like borrow() and return_book().

Make a class for BankAccount to practice deposits and withdrawals.

If you enjoyed this lesson, follow my blog for more beginner-friendly Python tutorials!

🐍 Python Lesson: Understanding Classes and Objects with Real Examples Part - 1 :