ReactJS - Introduction and Features
Tags: javascript, react, beginners, webdev
Published: 2022-12-25 18:16:15

**ReactJS** is a JavaScript library for building user interfaces.
ReactJS is a declarative, efficient, and flexible JavaScript library for building reusable UI components. It is an open-source, component-based front-end library responsible only for the view layer of the application

**ReactJS** application is made up of multiple components, each component responsible for outputting a small, reusable piece of HTML code. The components are the heart of all React applications. These Components can be nested with other components to allow complex applications to be built of simple building blocks.

**ReactJS** uses a virtual DOM-based mechanism to fill data in HTML DOM. The virtual DOM works fast as it only changes individual DOM elements instead of reloading the complete DOM every time.

**ReactJS Features**

We are going to look into the following top features of react :-

- JSX
- Components
- One-way Data Binding
- Virtual DOM
- Simplicity
- Performance

**JSX**
No one would have thought that HTML could co-exist with JavaScript and that too in a single syntax. Yes, that’s possible, which is why JSX is one of the important ReactJS features. JSX is the combination of JavaScript and XML while bearing a close resemblance to HTML.

**Components**
ReactJS is all about components. ReactJS application is made up of multiple components, and each component has its own logic and controls. These components can be reusable which helps you to maintain the code when working on large-scale projects.

**One-way Data Binding**
React supports one-way data binding which means a unidirectional data flow.
Unidirectional data flow means that data has one, and only one, way to be transferred to other parts of the application. In React this means:
The state is passed to the view and child components
Actions are triggered from the view and in turn, update the state

**Virtual DOM**
DOM stands for ‘Document Object Model’. In simple terms, it is a structured representation of the HTML elements that are present in a webpage or web app. A Virtual DOM is a “virtual” representation of the actual DOM. By virtual, it means a much lighter replica of the actual DOM in the form of objects that can be saved in the browser memory.
The Virtual DOM allows developers to not worry about state transitions. Once we update the state, ReactJS ensures the DOM matches that state.

**Simplicity**
The JSX file is applied by ReactJS, which further executes the application. With this, the process gets simplified, whether it is about coding or UI development. Alongside this, it helps in understanding the code better. Most importantly, with a component-based approach, ReactJS makes it possible to reuse the code effectively.

**Performance**
ReactJS is known to be a great performer. This feature makes it much better than other frameworks out there today. The reason behind this is that it manages a virtual DOM, Because of virtual DOM, the web application operates at a lightning speed as compared to other frameworks. Besides, the division of complex UI into unique elements makes it easy to boost development time.