ReactJS is an open-source JavaScript package that is used to create rich and interactive user interfaces. It enables the development of big and sophisticated online and mobile apps. The framework is known for its flexibility, scalability, and simplicity. It is now backed by the technical teams of Facebook and Instagram, as well as other specialists. The advantages of adopting React are its ability to work around a typical search engine failure to understand JavaScript-heavy apps like Yahoo, Bing, or Baidu.