JavaScript is the most used programming language with the largest open source repository in the world. It's practically everywhere, used by every type of software application. But many developers also find this language hard to understand. Given that in this article we're providing a short overview of the three books on JavaScript that will help to use this language productively. The books are published by O'REILLY. But what is really amazing is that the authors aren't just releasing these books, they have also given a free access to read them online on their websites.

1. Learning JavaScript Design Patterns by Addy Osmani

Addy Osmani works to make building apps on the web easier and holds the position as an engineering manager at Google particularly with the Chrome team. He also is associated with Progressive Web Apps and open-source libraries, and closely collaborating on improving web performance stories with React, Angular, Ember and Webpack. Addy Osmani appears to be an author of a few open source projects like Yeoman, TodoMVC, Material Design Lite and Web Starter Kit, that can be found on GitHub, and the two books - Learning JavaScript Design Patterns and Backbone.js Apps - both published with O'Reilly. He's also involved in blogging.

Design patterns, because of being a reusable solutions to commonly occurring problems in software design, are a fascinating topic to look into. And "Learning JavaScript Design Patterns" specifically targets professional developers who want to improve their knowledge of classical and modern design patterns. Here you can also find the ways they can be applied to the programming language and how you can keep your code maintainable, efficient and up-to-date. This book walks the sophisticated JavaScript developers through many other essential topics, including modern module formats and how to effectively namespace code.

2. Speaking Javascript by dr. Axel Rauschmayer

Dr. Axel Rauschmayer has been developing web applications since 1995 and programming even longer. He specializes in JavaScript and has followed its state and future since its creation. He has also done an extensive research into programming language design. Axel Rauschmayer writes a blog at 2ality.com and teaches classes for Ecmanauten. He also organizes the MunichJS user group and holds talks and workshops at conferences.

"Speaking JavaScript" guides the audience of programmers who already know object-oriented programming into and through JavaScript. It's no wonder that this book has been written by an experienced programmer for those who actually understand what he's talking about. There're four sections in this book: JavaScript quick start; JavaScript in depth; Background; and Tips, tools, and libraries. Every each one of them is set up to help you learn JavaScript starting with quick basics, moving through language features and its history (for those who want to understand also the connection of JavaScript to other languages) to the ending with some useful tips and descriptions of tools in an easy-to-read manner.

3. Programming JavaScript Applications by Eric Elliott

Eric Elliott is a JavaScript application architect, author, consultant, and a frequent public speaker who leaves in San Francisco. He's also a contributor to a software experiences for Adobe Systems, The Wall Street Journal, BBC and others, and some of the top recording artists, such as Metallica and Frank Ocean.

"Programming JavaScript Applications" covers a lot of ground quickly. This book doesn't intend to teach you the basics of JavaScript as it hasn't been written for beginners, it's for those who have some experience with JavaScript and know something about programming, but want to gain more skills. So, if you want to learn how to apply the powerful JavaScript features and test-driven development (TDD) techniques then this book is for you. The author shows how, without negatively affecting you code, to add client- and server-side features to a large JavaScript application.

Conclusion

So, these were the three O'Reilly books about JavaScript that we and many people online have considered to be great and very useful. Despite the fact that books are free to read online, they are also available for purchase on the website. So, on condition that one of them appealed to you in any way, you might consider buying it to appreciate the author’s work. If you have any comments about these books or you want to point out the book that you think we've missed, please, leave your feedback.

Also, if you're looking for some other books online, O'Reilly has a section of free books on their site. Enjoy reading and learning JavaScript.