🔶 JavaScript Variables & Data Types

Variables store data. JavaScript has different data types like numbers, strings, booleans, and more. Let’s get familiar!

📚 Example 1: Declaring Variables

// Using let and const
let name = "Alex";      // string
const age = 22;         // number
let isStudent = true;   // boolean

console.log("Name:", name);
console.log("Age:", age);
console.log("Student?", isStudent);

Output will appear here...

📂 Example 2: Data Types & typeof

// Check data types
console.log(typeof "Hello");       // string
console.log(typeof 123);           // number
console.log(typeof true);          // boolean
console.log(typeof undefined);     // undefined
console.log(typeof null);          // object (weird JS quirk)
console.log(typeof {name: "Sam"}); // object
console.log(typeof [1, 2, 3]);    // object (arrays are objects!)

Output will appear here...

⚡ Quick Tips

let is for variables you want to change later.
const is for constants — they can’t be reassigned.
JavaScript is loosely typed, so variables can change types but avoid doing that to keep your code clean.
Arrays and objects are technically of type "object".
null is a weird quirk — typeof null returns "object".

💡 Pro Tip: Use typeof to debug data types while coding.