React stormed the JS world several years ago to become its definite leader. React encourages you to use a reactive approach and a functional programming paradigm. React also introduced many of its own concepts to define its unique (at the time it was created) approach to frontend web development. To use React, you’ll have to master a component-based architecture, JSX, and unidirectional data flow. The unidirectional data flow is implemented by Flux.

React-based applications are divided into multiple components. A single component file contains both business logic and HTML mark-up (which is actually a JSX mark-up that’s transformed into JavaScript functions). For communication between components, you can use either Flux or a similar JS library. React also introduced special objects – state and props. Using the state and props objects, you can simply pass data from a component to the layout (using the state object) or from a parent component to a child component (using the props object).