1// javascript comment

1 // use '//'

1render() {
2  return (
3    <div>
4      <!-- This doesn't work! -->
5    </div>
6  )
7}

1<script type="text/javascript">
2<!--
3// This is a single line JavaScript comment
4
5document.write("I have comments in my JavaScript code!");
6//document.write("You can't see this!");
7//-->
8</script>
9
10

1New empty HTML comment wherever:  Shift + Alt + A

1// For single line comment
2
3/* For block of lines comment
4...
5...
6*/