React JS

What is ReactJS?

React.js is a front-end JavaScript framework developed by META (Facebook). To build composable user interfaces predictably and efficiently using declarative code, we use React. It’s an open-source and component-based framework responsible for creating the application’s view layer. 

ReactJs follows the Model View Controller (MVC) architecture, and the view layer is accountable for handling mobile and web apps.

React is famous for building single-page applications and mobile apps.

ReactJS Features

1. JSX - JavaScript Syntax Extension

JSX is a preferable choice for many web developers. It isn't necessary to use JSX in React development, but there is a massive difference between writing react.js documents in JSX and JavaScript. JSX is a syntax extension to JavaScript. By using that, we can write HTML structures in the same file that contains JavaScript code.

2. Unidirectional Data Flow and Flux

React.js is designed so that it will only support data that is flowing downstream, in one direction. If the data has to flow in another direction, you will need additional features. React contains a set of immutable values passed to the component renderer as properties in HTML tags. The components cannot modify any properties directly but support a call back function to do modifications. 

3. Virtual Document Object Model (VDOM)

React contains a lightweight representation of real DOM in the memory called Virtual DOM. Manipulating real DOM is much slower compared to VDOM as nothing gets drawn on the screen. When any object’s state changes, VDOM modifies only that object in real DOM instead of updating whole objects. 

That makes things move fast, particularly compared with other front-end technologies that have to update each object even if only a single object changes in the web application.

4. Extensions

React supports various extensions for application architecture. It supports server-side rendering, Flux, and Redux extensively in web app development. React Native is a popular framework developed from React for creating cross-compatible mobile apps.

5. Debugging

Testing React apps is easy due to large community support. Even Facebook provides a small browser extension that makes React debugging easier and faster.

Next, let’s understand some essential concepts of ReactJS.