Difference between == and ===

Question

What’s the difference between == and ===?

Answer

• == performs type coercion before comparison
• === checks both type and value

console.log(5 == '5'); // true (string converted to number)
console.log(5 === '5'); // false (different types)

Type coercion pitfalls:

console.log(0 == false); // true
console.log('' == false); // true
console.log([] == false); // true

Real-World Example

Always use === in conditions — coercion often leads to hidden bugs.

Quick Practice

Predict:

console.log(null == undefined);
console.log(null === undefined);

Summary

===is safer, predictable, and modern — it’s how professionals compare in JavaScript.