What is React js?

Introduction

React is a web application development technology in JavaScript, which was created by Facebook. It is a free and open source framework whose main objective is the development of dynamic interfaces for Web pages.
React is known for its focus on building reusable components, which allows developers to create complex and scalable user interfaces in a more efficient way. React components can be combined to create a complete application, and can be updated efficiently and without affecting application performance.

React is a free and Open Source Frontend Framework.

React is a framework for building user interfaces. It is used to build high-performance and scalable web applications. It is an alternative to other JavaScript libraries such as AngularJS, Ember and Vue.

React uses the virtual DOM to make it easy for developers to build large web applications using data-intensive components that can be reused throughout the application.

The main feature of React is its ability to respond to changes.

React is based on JavaScript and is used by companies such as Facebook, Instagram and Netflix.

React has a few core concepts:

Components are the basic building blocks of your application. You can think of them as functions that return a virtual DOM tree or an actual DOM node (rendered by React). This makes it very easy to modularize your code base into reusable components that can be composed together into more complex ones.
Stateless functional components are basically function-oriented versions of stateful class-based components: they don’t have their own internal state but allow you to pass properties of the parent components through props. They’re great when you want something quick and dirty without the need for state management.

To build an application that works well on multiple platforms and is fast or interactive, the MVVM (Model-View-ViewModel) pattern is useful because it allows you to make changes to models without harming the user’s presentation.

Conclusion

If you are looking for a tool for web application development, you should definitely consider React.