how do you add a comment i javascript code example

Example 1: javascript comment

//This is a javascript single line comment

/*
And here is a
multiline comment
*/

Example 2: comment out in javascript

<script type="text/javascript">
<!--
document.write("I have multi-line comments!");
/*document.write("You can't see this!");
document.write("You can't see this!");
document.write("You can't see this!");
document.write("You can't see this!");
document.write("You can't see this!");
document.write("You can't see this!");
document.write("You can't see this!");*/
//-->
</script>