Facebook's React, a JavaScript framework for building SPAs, is incredibly popular, and has constantly been receiving a lot of attention from the community. Additionally, React spreads out to mobile apps via React Native, as well as 3D and VR via React 360.

React was released to the public in 2013 and has revolutionized the way you build web apps. React is essentially a JavaScript-based view library, focusing on building encapsulated and reusable components, and its format was considered a novel approach at the time.

Similar to Angular, React is highly opinionated, although it focuses on a single aspect of building an app, which is the view engine, that is, components. Along with React comes JSX, enabling you to write the user interface template code combined with the logical code, but more on that later in this chapter.