Learn the key concepts behind React and how to use JSX elements and components to build lean and fast web front ends React, also known as ReactJS, is an open source JavaScript library for building ...

React.js Fundamentals is a free course, offered along with another course (ES6/7 for React, $45) and some upcoming paid courses in McGinnis' React.js Program. The Learn React.js: The Basics course ...

Figure 1. Web apps are built in HTML, CSS, and JavaScript. It doesn’t matter whether your web app was written using React or some other library, such as Angular, Knockout, or jQuery.

Beyond the usual quick tips, let's look at both the business case and the technical side of keeping React bundles lean.