title: import App from './App';
body: <p>I am trying react based on <a href="https://github.com/facebookincubator/create-react-app" rel="nofollow noreferrer">create-react-app</a>. I'm new to react.</p>
  
  <p><strong>index.js</strong></p>
  
  <pre><code>import React from 'react';
  import ReactDOM from 'react-dom';
  import App from './App';
  
  ReactDOM.render(
    &lt;App /&gt;,
    document.getElementById('root')
  );
  </code></pre>
  
  <p><strong>./App</strong> in <code>import App from './App';</code> is not clear to me when and where is this created, is this done by babel? </p>
  
  <p><strong>file strucutre</strong></p>
  
  <pre><code>my-app/
    README.md
    node_modules/
    package.json
    .gitignore
    public/
      favicon.ico
      index.html
    src/
      App.css
      App.js
      App.test.js
      index.css
      index.js
      logo.svg
  </code></pre>
  
  <p><strong>App.js</strong></p>
  
  <pre><code>import React, { Component } from 'react';
  
  class App extends Component {
    render() {
      return (
       &lt;div&gt;myComponent&lt;/div&gt;
      )
    }
  }
  
  export default App;
  </code></pre>