Client-side (i.e., JavaScript) frameworks and libraries are all the rage — which shouldn’t come as a surprise, given the ubiquity of the browser and of Web-based applications. Facebook has developed, and is promoting, React.js,  a JavaScript framework that they are using for many applications, and which has become  popular since its release. In this talk, two of the React.js developers, Tom Occhino and Jordan Walke, introduce and describe the framework — starting with its motivations, and continuing to its use in real-life applications.