A class in JavaScript is a template (or blueprint) for creating objects with shared structure and behavior.
It allows us to define properties and methods that every object created from that class will have.

I created a JavaScript class called Product to model real-world items with a name and a price. This class includes methods to display product details and calculate the total cost including tax.

class Product{
    constructor(name, price){
        this.name = name,
        this.price = price
    }

    displayProduct(){
        console.log(`Product: ${this.name}`),
        console.log(`Price: Ksh${this.price}`)
    }

    calculateTotal(salesTax){
        return this.price + (this.price * salesTax)
    }
};

const salesTax = 0.05;

const product1 = new Product("Shirt", 25.80);
const product2 = new Product("Dress", 19.50);

product1.displayProduct();
product2.displayProduct();

const total = product1.calculateTotal(salesTax);
console.log(`The total is: Ksh${total.toFixed(2)}`);

class Product {
  constructor(name, price) {
    this.name = name;
    this.price = price;
  }
  .......
}

• I used the constructor method to initialize each product's name and price. Every time I create a new product using new, these values are automatically assigned to that object via this.

{
  .......
  displayProduct() {
    console.log(`Product: ${this.name}`);
    console.log(`Price: Ksh${this.price}`);
  }

  calculateTotal(salesTax) {
    return this.price + (this.price * salesTax);
  }
}

I added two instance methods:

• displayProduct() logs the product's name and price.
• calculateTotal(salesTax) returns the final price after adding a given percentage of sales tax.

Both methods use this to access the product’s own properties.

const product1 = new Product("Shirt", 25.80);
const product2 = new Product("Dress", 19.50);

• I used the new keyword to create two product objects: one for a shirt, and one for a dress. Each object now contains its own name, price, and has access to the methods I defined.

product1.displayProduct();
product2.displayProduct();

const total = product1.calculateTotal(salesTax);
console.log(`The total is: Ksh${total.toFixed(2)}`);

I printed the details of each product using displayProduct(). Then, I calculated the total price of product1 by applying a 5% sales tax and displayed the result formatted to two decimal places using toFixed(2).

1. How to define and use JavaScript classes using the class keyword.
2. How to set up a constructor to initialize properties using this.
3. How to define and use instance methods inside a class.
4. The importance of the this keyword in referring to the current object.
5. How to create new objects (instances) from a class using the new keyword.
6. How to pass arguments to methods and use return values.
7. How to format numerical output using .toFixed(2) for currency display.