React.js uses isomorphic web design . Isomorphic web design is an approach which is gaining strength. In this method it dynamically generates HTML using server or client rendering based on the approach gains the best experience for visitors. Server rendered pages will load very fast if its built correctly. React is able to render the requested page on the server before sending it to the client. This page will be indexed like other static pages. This is a main reasons to consider React as good for SEO. Server rendering is done using ReactDOMServer.renderToString. When someone visits the page he will get an already rendered page of markup. React will add the event bindings instead of replacing the content when ReactDOM.render is called. Then the React application will take over and render the other pages. Universal JavaScript or Universal React is becoming a term for JavaScript applications that use single code base for render on both server and client. Google another search engines index single page apps if they only render on the front-end. Server Side Rendering is a good method to get your initial page loading faster. Read more
