JavaScript Basics: Variables and Data Types

Variables allow us to store and manage data in our code. JavaScript has several types of data we can work with, like strings, numbers, and booleans.

Declaring Variables

In JavaScript, we use let, const, or var to declare variables:

      
        let age = 25;
        const name = "John";
        var isStudent = true;
      
    

Data Types

• String: Text data, written with quotes ("Hello" or 'Hello').
• Number: Numeric data, can be integers or decimals (e.g., 42 or 3.14).
• Boolean: True or false values (true or false).

Example: Variables and Data Types

      
        let message = "Hello, World!";
        const pi = 3.14;
        var isOpen = true;
        console.log(message, pi, isOpen);
      
    

Activity

Quiz