HTML Comments - SwatiMaurya08/html-notes GitHub Wiki

HTML Comments

Comment is a piece of code which is ignored by any web browser. It is a good practice to add comments into your HTML code, especially in complex documents, to indicate sections of a document, and any other notes to anyone looking at the code. Comments help you and others understand your code and increases code readability.

HTML comments are placed in between <!-- ... --> tags. So, any content placed with-in <!-- ... --> tags will be treated as comment and will be completely ignored by the browser.

Example:

<!DOCTYPE html>
<html>

   <head>  <!-- Document Header Starts -->
      <title>This is document title</title>
   </head> <!-- Document Header Ends -->
	
   <body>
      <p>Document content goes here.....</p>
   </body>
	
</html>

Multiline Comments

So far we have seen single line comments, but HTML supports multi-line comments as well.

You can comment multiple lines by the special beginning tag <!-- and ending tag --> placed before the first line and end of the last line as shown in the given example below.

Example:

<!DOCTYPE html>
<html>

   <head>  
      <title>Multiline Comments</title>
   </head> 
	
   <body>
      <!-- 
         This is a multiline comment and it can
         span through as many as lines you like.
      -->
      
      <p>Document content goes here.....</p>
   </body>
	
</html>

Conditional Comments

Conditional comments only work in Internet Explorer (IE) on Windows but they are ignored by other browsers. They are supported from Explorer 5 onwards, and you can use them to give conditional instructions to different versions of IE.

Example:

<!DOCTYPE html>
<html>

   <head>  
      <title>Conditional Comments</title>

      <!--[if IE 6]>
         Special instructions for IE 6 here
      <![endif]-->
   </head> 
   
   <body>
      <p>Document content goes here.....</p>
   </body>
	
</html>

Using Comment Tag

There are few browsers that support <comment> tag to comment a part of HTML code.

Note − The <comment> tag deprecated in HTML5. Do not use this element.

Example:

<!DOCTYPE html>
<html>

   <head>
      <title>Using Comment Tag</title>
   </head>
	
   <body>
      <p>This is <comment>not</comment> Internet Explorer.</p>
   </body>
	
</html>

Commenting Script Code

Though you will learn JavaScript with HTML, in a separate tutorial, but here you must make a note that if you are using Java Script or VB Script in your HTML code then it is recommended to put that script code inside proper HTML comments so that old browsers can work properly.

Example:

<!DOCTYPE html>
<html>

   <head>
      <title>Commenting Script Code</title>
      
      <script>
         <!-- 
            document.write("Hello World!")
         //-->
      </script>
   </head>
	
   <body>
      <p>Hello , World!</p>
   </body>
	
</html>

Output:

Hello World!
Hello , World!
⚠️ **GitHub.com Fallback** ⚠️