Learn modern JavaScript end to end — the only language the web runs natively.

Welcome to JavaScript: The Language of the Web.

JavaScript is the language of the web — the only one browsers run natively — and, through Node.js, a language for servers and tools too. This free, example-driven book teaches modern JavaScript from the ground up: running code in the browser and Node, the type system and its coercion quirks, control flow, functions and closures, objects and arrays, prototypes and classes, the DOM and events, and the part everyone must master — asynchronous programming with the event loop, promises, and async/await — closing with modern ES features, modules, error handling, and the Node/npm ecosystem. Eleven focused chapters with runnable code and clear diagrams. Learn the most widely used language in software.

This title is part of the ShriIra library and is free to read in full, right here — our small contribution to making world-class knowledge easy to reach.

A note on reading it: open the Contents menu at the top of the reader to jump between chapters, use the Aa menu to set a comfortable text size, theme (light, sepia, or night), and single- or two-page layout. Your place is saved automatically, so you can always pick up where you left off.

We hope it serves you well.

— Shriira Press

Contents

1. Chapter 1 — What JavaScript Is
2. Chapter 2 — Getting Started
3. Chapter 3 — Variables, Types, and Operators
4. Chapter 4 — Control Flow and Loops
5. Chapter 5 — Functions and Closures
6. Chapter 6 — Objects and Arrays
7. Chapter 7 — Prototypes, Classes, and this
8. Chapter 8 — The DOM and Events
9. Chapter 9 — Asynchronous JavaScript
10. Chapter 10 — Modern JavaScript and Modules
11. Chapter 11 — Errors, Node, and Good Practice