• When programs grow bigger, writing everything as loose variables and functions becomes messy. Imagine managing a school system, a car dealership, or even a game using scattered variables everywhere. Even thinking about it makes head spin.

• This is where Object-Oriented Programming (OOP) helps.

• OOP is a programming approach where we structure our code around objects that represent real-world things.

In short:

Instead of writing random code, we organize code the way the real world works.

Real-World Analogy: Blueprint → Objects

• Before a car is manufactured, engineers design a blueprint.

• That blueprint defines:

1. Engine

2. Wheels

3. Color

4. Speed

• But the blueprint itself is not a car.

• From the same blueprint, we can produce thousands of cars.

Blueprint → Objects Visualization

In programming:

Concept	Real World	Programming
Blueprint	Car design	Class
Manufactured car	Physical car	Object

So we can create many objects from one class.

What Is a Class in JavaScript?

• A class is like a blueprint used to create objects. Basically a mold for mass production of statues. I might have made it worse, nevermind, just code for a bit and you would understand it.

• A Class defines:

• What properties objects will have

• What actions (methods) they can perform

Example:

class Person {

}

• Right now, this class doesn't do anything yet — it's just an empty blueprint.

Creating Objects Using Classes

Once we have a class, we can create objects using the new keyword.

Example:

class Person {}

const person1 = new Person();
const person2 = new Person();
//2 objects person1 and person2, stupid variable names must be forgiven

Here:

• person1 and person2 are objects

• Both were created from the Person class

It's like building two houses using the same architectural design.

Constructor Method

• The constructor is a special method that runs when we create an object.

• It helps initialize the object's properties.

Example:

class Person {

  constructor(name, age) {
    this.name = name;
    this.age = age;
  }

}

Explanation:

• this refers to the current object, it's actually very important.

• Each object will get its own values.

Creating objects:

const person1 = new Person("Rahul", 25);
const person2 = new Person("Anita", 22);

Now:

person1 → Rahul, 25
person2 → Anita, 22

Congratulations. We just manufactured two humans in JavaScript.

Methods Inside a Class

• Methods are functions inside a class. Methods are basically functions that are built in the class code.

• They describe what an object can do.

Example:

class Person {

  constructor(name, age) {
    this.name = name;
    this.age = age;
  }

  greet() {
    console.log("Hello, my name is " + this.name);
  }

}

Create an object:

const person1 = new Person("Rahul", 25);
person1.greet();

Output:

Hello, my name is Rahul

Now our objects can introduce themselves.

Finally, JavaScript objects have better manners than most people on the internet.

---

Example: Car Class

• Let’s look at another simple example. Final One, I promise.

class Car {

  constructor(brand, speed) {
    this.brand = brand;
    this.speed = speed;
  }

  drive() {
    console.log(this.brand + " is driving at " + this.speed + " km/h");
  }

}

Create objects:

const car1 = new Car("Tesla", 120);
const car2 = new Car("BMW", 150);

car1.drive();
car2.drive();

Output:

Tesla is driving at 120 km/h
BMW is driving at 150 km/h

• One blueprint → many cars.

Sadly, still no free Tesla.

---

Basic Idea of Encapsulation

Encapsulation simply means:

Keeping related data and functions together in one place.

Instead of writing random variables everywhere, we bundle them inside a class.

Example:

Without OOP:

let name = "Rahul";
let age = 25;

function greet() {
  console.log("Hello " + name);
}

With OOP:

class Person {

  constructor(name, age) {
    this.name = name;
    this.age = age;
  }

  greet() {
    console.log("Hello " + this.name);
  }

}

Everything related to Person lives inside the class. You can clearly see how much this can help.

This makes code:

• Easier to understand

• Easier to maintain

• Easier to reuse

And most importantly, it prevents the developer from shouting

“Where did I define that variable?!” at 2 AM.

---

Why OOP Is Useful

OOP helps developers:

• Organize code better

• Reuse code easily

• Represent real-world entities clearly

• Reduce repetition

Instead of rewriting the same code for every new object, we just create new instances from the class.

Programmers call this code reusability.

Managers call this productivity.

Class → Object Relationship

Visual Representation

Conclusion

I think, well hope you learnt a little bit more about objects today. I hope you a beautiful summer.

Last but not least, I am grateful to the #chaicode team. Couldn't have done this without the community.