title: Compiling with Babel: Is a preset-flag necessary when having a .babelrc-file?
body: <p>I have learned and used the following syntax for compiling JavaScript-files using Babel:</p>
  
  <pre><code>babel main.js -o bundle.js --presets es2015
  </code></pre>
  
  <p>I haven't known about the existence of .babelrc-files until today.</p>
  
  <p>Now my question ...</p>
  
  <p>If I have a .babelrc-file with the following content:</p>
  
  <pre><code>{
      "presets": ["es2015"]
  }
  </code></pre>
  
  <p><strong>Is the ' --preset es2015 ' flag still necessary when compiling from the command  line?</strong></p>
  
  <p><strong>Or can I leave it? Just having ' babel main.js -o bundle.js '?
  And Babel takes the further configuration out of the .babelrc-file?</strong></p>