React JS

React.js is an open-source JavaScript library developed by Facebook for building dynamic and interactive user interfaces, particularly for single-page applications. It simplifies the process of creating UIs by using a component-based architecture, where the user interface is broken into small, reusable pieces called components. Each component can manage its own state and logic, making complex applications easier to develop and maintain.

React employs a Virtual DOM, a lightweight copy of the real DOM, which ensures efficient updates and rendering. When the state of an application changes, React updates only the affected parts of the DOM, leading to better performance. JSX, a syntax extension for JavaScript, allows developers to write HTML-like code within JavaScript, improving readability and ease of development.