Modern JavaScript (ES2024+): Modern Syntax, Async/Await & Event Loop

By Elena Rostova • Beginner • 11 min read • Updated 2026-09-11

What You Will Master in This Tutorial

Master safe property traversal with Optional Chaining and Nullish Coalescing.
Understand deep object cloning with native structuredClone().

1. Nullish Coalescing and Optional Chaining

Before ES2020, developers used logical OR for defaults. Modern JavaScript solves this with ?? and ?.

JAVASCRIPT

const apiResponse = { user: { profile: { points: 0 } } };
const score = apiResponse.user?.profile?.points ?? 100;
console.log(score); // 0 (correctly preserved)

Note: Use ?? whenever 0 or false are valid domain values.

Knowledge Check: Test Your Understanding

1. What is the difference between || and ?? in JavaScript?

Frequently Asked Questions

How do I deep clone an object without lodash?

Use structuredClone(obj), which is now natively supported across all modern runtimes.