What is React Js? Why it is so popular in now days?
What is React Js? React is a JavaScript library for building user interfaces. It was developed by Facebook and is now maintained by Facebook and a community of individual developers and companies. React focuses on building reusable UI components and managing the state of these components efficiently. React allows developers to build UI components as a function of the component's state, which is an object that represents the component's data. React automatically re-renders a component when its state changes, ensuring that the component's view is always up-to-date. This makes it easier to build complex, dynamic UIs and helps prevent bugs that can result from manually managing the state of a component. React uses a virtual DOM (Document Object Model) to increase the performance of updates. The virtual DOM is a lightweight in-memory representation of the actual DOM, and React uses this representation to calculate the minimal amount of DOM updates that are necessary when the