Understanding Data Types in JavaScript

Explanation:

In JavaScript, a "data type" is the kind of information you're working with. It's like how you have different types of things in real life—like a book, a toy, or a pencil. Each one is different and used in different ways.

In JavaScript, there are Primitive Data Types (simple ones) and Non-Primitive Data Types (more complex ones).

Primitive Data Types

1. String: Think of this as words or text. You write it in quotes.

let name = "Satyendra";

Here, "Satyendra" is a string.

2. Number: These are just numbers, like how you count things.

let age = 25;

25 is a number.

3. BigInt: This is for super big numbers that normal numbers can't handle.

let bigNumber = 12345678901234567890n;

The n at the end makes it a bigint.

4. Boolean: This is either true or false, like a light switch that can be ON (true) or OFF (false).

let isStudent = true;

true is a boolean.

5. Undefined: This means you haven’t put anything in the box yet—it’s empty.

let job;

job is undefined because we haven’t put anything in it yet.

6. Null: This is an empty value, meaning "nothing is here."

let car = null;

car is null because we’ve said there’s nothing in it.

Code Example 1 (Primitive Data Types):

let name = "Alice";        // string
let age = 10;              // number
let isHappy = true;        // boolean
let largeNumber = 123456789n;  // bigint
let color;                 // undefined
let favoriteFood = null;   // null

Explanation for Code Example 1:

We have six variables: name is a string holding the value "Alice." age is a number with the value 10. isHappy is a boolean with the value true, meaning yes. largeNumber is a really big number (bigint). color is undefined because we didn’t give it a value yet. favoriteFood is null, which means there’s nothing in that box for now.

Non-Primitive Data Type

Object: This is more complex—it can hold many different things inside, like a backpack with different items.

let person = {
    name: "Alice",
    age: 10,
    isStudent: true
};

Here, person is an object with three pieces of information: name, age, and isStudent.

Code Example 2 (Non-Primitive Data Type - Object):

let car = {
    brand: "Toyota",
    model: "Corolla",
    year: 2022,
    isElectric: false
};

Explanation for Code Example 2:

car is an object. Think of it like a backpack that holds many things: The brand is "Toyota." The model is "Corolla." The year is 2022. And isElectric is false, meaning the car is not electric.

Objects are used when you want to group lots of information together in one place.