React router 是如何工作的以及 link 和 Route 之间的区别是什么

Javascript
import React from 'react';
import { BrowserRouter as Router, Route, Link } from 'react-router-dom';
const Home = () => <h1>首页</h1>;
const About = () => <h1>关于我们</h1>;
const Contact = () => <h1>联系我们</h1>;
const App = () => {
  return (
    <Router>
      <nav>
        <ul>
          <li>
            <Link to="/">首页</Link>
          </li>
          <li>
            <Link to="/about">关于我们</Link>
          </li>
          <li>
            <Link to="/contact">联系我们</Link>
          </li>
        </ul>
      </nav>
      <Route path="/" exact component={Home} />
      <Route path="/about" component={About} />
      <Route path="/contact" component={Contact} />
    </Router>
  );
};
export default App;