The Little JavaScript Book Cover

All you need to know about JavaScript (but never dared to ask).

Ever dreamed of a JavaScript book focused on those hard to grasp concepts, but beginner friendly?

If you answered yes then you will love "The Little JavaScript Book".



The book is organized in three parts. The first part covers the inner working of JavaScript engines and the "hard parts" of the language: closures, the prototype system, this and new.

Every chapter can be consumed as a stand-alone episode, tackling down a group of topics that in my mind played nicely together.

The second part of the book has a lot of practical exercises on the DOM while covering code organization and best practices. In chapter 8, 9, 10, and 11 for example you'll build small features while touching Promises, DOM manipulation, JavaScript classes, localStorage, TypeScript, and more.

Every chapter ends with quizzes and exercises, useful for making the concepts stick. The third and last part contains solutions and hints for the exercises and future additions to the book. At the last minute I decided to add a chapter on TypeScript + JSDoc. TypeScript is gaining a lot of traction: more and more developers are switching from JavaScript to TS.



The book starts with a brief introduction on JavaScript fundamentals:

  • variables
  • functions
  • type and primitives
  • terminology
  • and much more!


After the introduction I'll cover the hard parts of JavaScript, like:

  • JavaScript engines
  • event loop and the call stack
  • closures
  • the "new" keyword
  • this in JavaScript
  • Promises and async/await
  • the prototype system


The rest of the book is dedicated to:

  • DOM manipulation
  • XMLHttpRequest and Fetch
  • working with forms
  • code organization and documentation
  • TypeScript and JSDoc
  • 40+ quiz and exercises
  • debugging
  • a collection of JavaScript recipes
  • and much more!
JavaScript engines: the big picture with the Event Loop
Learn JavaScript engines with illustrations


"Why another JavaScript book?"

As much as I love "You don't know JS" and "Eloquent JavaScript" I feel there is the need for a book which takes the reader by hand.

Also, everyone has a unique viewpoint on technical topics and my readers love my style of teaching.

"The Little JavaScript Book" aims to be a reference on the hard parts of JavaScript, written with beginners in mid.

When the book will be released? How much will it cost?

I hope to release the book by the end of November 2019.

I will be available on Leanpub for a fair price. If you live in a country with low purchase power you can get a copy free from this page.

Who the book is for?

While writing the book I had in mind web developers who always worked with jQuery or JavaScript without digging deeper into the language. The book is not a complete intro to programming but with a little work you should be able to follow along even if you never programmed before.

I highly suggest reading the book even if you're an experienced JavaScript programmer or you're coming from another language. You may be surprised how much you forgot about JavaScript.

Ready to roll?

Valentino Gagliardi

The author

I am Valentino Gagliardi and I help busy people embracing this crazy modern JavaScript stuff.

I do training and consulting on JavaScript, React, Redux.

I write a lot: one of my best articles is React Redux Tutorial for Beginners: The Definitive Guide. Mark Erikson (Redux mantainer) mentions it as one of the best resources for learning Redux.

I write books too! Check out:

I'm also active in the Python community. I serve as a coach for Django Girls and I've spoke at Pycon Italia. Check out my talks here.