React is another popular JavaScript library for building user interface (UI) components for web applications. In contrast to Angular, React uses composable components in instead of template logic. When using composable components your logic is not in a separate template file. The technique of not introducing any logic into the template is achieved through a technique called JSX (JavaScript syntax extension). JSX is an HTML-like syntax that compiles down to JavaScript.

Probably the easiest way to get started with React is to include the necessary libraries from a CDN. React supports most popular browsers, including Internet Explorer 9 and above. React's documentation points you to a JSFiddle Hello World example to start hacking React. You can find this JSFiddle at the following URL: https://jsfiddle.net/reactjs/69z2wepo/. This example only prints "help world".

As this book is about Bootstrap, I cannot discus JSX in detail here. You can learn more about React and...