The ReactJS library was originally created by Facebook developers to solve code maintenance issues. Its developers have also created excellent documentation for the React framework. ReactJS is based on HTML, which is the main structure of web pages. Browsers create a Document Object Model (DOM) from HTML elements. Its virtualization helps the code run quickly and efficiently with minimal number of updates. To improve the performance of your application, you should learn how to use ReactJS.

React provides a useful method called setState, which enqueues updates to a component’s state and instructs the browser to re-render the component. In the example above, a subscription button must change its message. To change its message, the subscribe button method uses setState(). The subscribe button method, changeMessage, uses the setState() method. It also calls the updateMessage() method, which changes the value of a sub.

When working on a complex project with React, the user should not place application logic into presentation components. Instead, the user should use reusable components. They can implement interaction with users and send input to other components. One important thing to remember is not to call the parent API directly unless it is absolutely necessary. A parent component can give a child a function reference, which is used to invoke that function without knowing the name of the parent.

React JS uses a virtual DOM to maintain track of all the elements on a page. In addition to saving on page load time, it also makes the user’s experience much smoother. React creates a virtual DOM for JSX elements, which is essentially a JavaScript representation of the DOM. Using this virtual DOM, a web page can update dynamic content and user interaction without having to reload the entire page.