React, also known as ReactJS, is an open source JavaScript library for building user interfaces, often for single-page applications or to add interactive views to existing web applications built ...

Now, here’s where the special nature of React comes in. Besides normal HTML, CSS, and JavaScript, the bulk of your React code will be written in JSX.

One is a young, free upstart offering. One costs money and is part of a comprehensive, established online learning site. Here's a comparison of my experiences with React.js Fundamentals by Tyler ...