What are the key features of React?

React, a popular JavaScript library for building user interfaces, has several key features:

1. Component-Based Architecture: React uses a component-based approach where the UI is divided into reusable components. Each component manages its own state and renders the UI based on its state.

2. Virtual DOM: React uses a virtual DOM to efficiently update the real DOM. It minimizes direct manipulation of the DOM by comparing the virtual DOM with the real DOM and updating only the parts that have changed.

3. Declarative Syntax: React allows developers to describe what the UI should look like based on the application’s state. React takes care of updating the UI when the state changes, making it easier to reason about and manage the UI.

4. JSX (JavaScript XML): JSX is a syntax extension that allows you to write HTML elements and components in JavaScript code. It makes it easier to create and visualize the component structure.

5. Unidirectional Data Flow: React enforces a one-way data flow where data is passed from parent to child components. This helps in maintaining a predictable data flow and makes debugging easier.

6. Hooks: Introduced in React 16.8, hooks are functions that let you use state and other React features without writing a class. Common hooks include useState, useEffect, and useContext.

7. Context API: The Context API allows you to manage global state and pass data through the component tree without having to pass props down manually at every level.

8. React Router: React Router is a library for handling routing in React applications, allowing you to create single-page applications with navigation between different views.

9. Server-Side Rendering (SSR): React supports server-side rendering, which can improve performance and SEO by rendering components on the server and sending the pre-rendered HTML to the client.

10. React Native: React Native is a framework for building mobile applications using React. It allows you to use the same React principles and components to create native mobile apps for iOS and Android.

These features contribute to React's flexibility, performance, and developer-friendly nature.