Using React JS is an easy way to update the state of your DOM without needing to reload the entire page. It also enables you to create reusable components that can be used throughout your application.

React uses a virtual DOM to keep track of component states. It monitors the changes made to data and compares the new state to the old one. The result is a fast and efficient web application.

React has two main component types. One is the wrapper component. These components provide a standard structure for displaying child components.

The other component type is the functional component. These components are declared with ES6 classes and include a render method. This method specifies how the component will be rendered to the DOM.

This component type is most useful when a single component needs to be used multiple times. For example, a subscribe button may need to change its display message.

In React, the change message method uses the setState method to update the values of a sub component. The best part is that the ChangeMessage method can be implemented in a single line of code.

The React library is a lot smaller than its competitors. In fact, when gzipped, it is less than 6kb. It also includes the JSX and Virtual DOM extensions. These extensions are used to optimize site performance.

The React Stack Overflow forum has more than 250k questions. Facebook has also released a Chrome extension to help debug React applications.