JavaScript Comparison Operators

== vs ===

== allows type coercion, === doesn't:

5 == '5';   // true (coerces types)
5 === '5';  // false (strict)

Always Use ===

null == undefined;  // true
null === undefined; // false

0 == false;  // true
0 === false; // false

Key Takeaway

Use === for strict comparison. Avoids type coercion bugs. Essential best practice.