What is React Router and how do you set it up? React Router क्या है और कैसे setup करें?

// React Router v6
import { BrowserRouter, Routes, Route } from 'react-router-dom';

function App() {
  return (
    <BrowserRouter>
      <Routes>
        <Route path='/' element={<Home />} />
        <Route path='/about' element={<About />} />
        <Route path='/user/:id' element={<User />} />
      </Routes>
    </BrowserRouter>
  );
}

// Using Link
import { Link } from 'react-router-dom';

function Navigation() {
  return (
    <nav>
      <Link to='/'>Home</Link>
      <Link to='/about'>About</Link>
    </nav>
  );
}