import App from './App';
<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>