Variables in JavaScript

Variables are containers for storing data values. In JavaScript, you can declare variables using var, let, or const.

Declaring Variables

let name = "John";
const age = 30;
var isStudent = true;

Data Types

JavaScript has several primitive data types:

• String - Text values like "Hello World"
• Number - Numeric values like 42 or 3.14
• Boolean - true or false values
• Undefined - A variable that hasn't been assigned a value
• Null - Intentional absence of any object value

Example

let greeting = "Hello";
let count = 10;
let isActive = true;

console.log(greeting); // Output: Hello
console.log(count);    // Output: 10
console.log(isActive); // Output: true