Chapter 1. Everything You Should Know About React

Hello, readers!

This book assumes that you already know what React is and what problems it solves for you. You may have written a small/medium application with React and you want to improve your skills and answer all your open questions.

You should know that React is maintained by developers at Facebook and hundreds of contributors within the JavaScript community.

React is one of the most popular libraries for creating user interfaces and it is well-known to be fast, thanks to its smart way of touching the DOM.

It comes with JSX, a new syntax to write markup in JavaScript, which requires you to change your mind regarding the separation of concerns. It has many cool features, such as the server-side rendering that gives you the power to write Universal applications.

To follow this book, you will need to know how to use the terminal to install and run npm packages in your Node.js environment.

All the examples are written in ES2015, which you should be able to read and understand.

In this first chapter, we will go through some basics concepts which are important to master to use React effectively, but are non-trivial to figure out for beginners:

• The difference between imperative and declarative programming
• React components and their instances, and how React uses elements to control the UI flow
• How React changes the way we build web applications, enforcing a different new concept of separation of concerns, and the reasons behind its unpopular design choice
• Why people feel the JavaScript Fatigue and what you can do to avoid the most common errors developers make when approaching the React ecosystem