Javascript comments

We usually use JavaScript comments for explaining JavaScript code and making it more readable. They also can be used to prevent execution during testing alternative code.

<script type="text/javascript">
<!--
  ...
  //-->
</script>

But we don’t use this method in modern JavaScript, because this kind of comments hide JavaScript code from old browsers. On the other hand, they can help you identify a really old code.

There are exists two types of comments: single line comments and multi-line comments. The example which you see here uses a single-line comment before each code line:

// javascript comments: welcome to w3Docs
<script>
  // console.log('Welcome to w3Docs!');
</script>

We use single line comments for writing small notes. You just need to add // before your code or text. Note that any kind of text between // and the end of the line will be ignored by JavaScript.

As concerns multi-line comments, there are long segments of code that we used to disable. You need to add /* before your code and */ after it. Start with /* and end with */. Remember, that any text between /* and */ will be ignored by JavaScript.

/* javascript comments:
	welcome to w3Docs
    */
<script>
  /*  console.log('Welcome to w3Docs!');
    alert("Hello.");    */
</script>



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