React is a JavaScript library for building user interfaces, maintained by Meta (Facebook). It uses a component-based architecture and virtual DOM to create interactive web applications efficiently.

Key Features

• Component-Based - Build reusable UI components
• Virtual DOM - Efficient rendering and updates
• JSX - Write HTML-like syntax in JavaScript
• Hooks - State and lifecycle management in functional components
• Ecosystem - Rich ecosystem of tools and libraries

Common Use Cases

• Web Applications - Single-page applications (SPAs)
• Interactive UIs - Dynamic, responsive user interfaces
• Component Libraries - Reusable UI component systems
• Mobile Apps - React Native for cross-platform mobile development

Getting Started

# Create a new React app
npx create-react-app my-app
cd my-app
npm start

# Or with Vite (faster)
npm create vite@latest my-app -- --template react
cd my-app
npm install
npm run dev

Basic Example

import React, { useState } from 'react';

function Counter() {
  const [count, setCount] = useState(0);

  return (
    <div>
      <h1>Count: {count}</h1>
      <button onClick={() => setCount(count + 1)}>
        Increment
      </button>
    </div>
  );
}

export default Counter;

Why Choose React?

React excels when you need:

• Component Reusability - Build once, use everywhere
• Performance - Virtual DOM optimizes rendering
• Developer Experience - Great tooling and debugging
• Community - Large ecosystem and job market
• Flexibility - Works with any backend or state management

React is the most popular frontend framework, making it ideal for web development and career growth.