Check out example codes for "commenting in html". It will help you in understanding the concepts better.

Code Example 1

<!-- your goes comment here -->

Code Example 2

<!-- Write your comments here -->

Code Example 3

<!-- this will be ignored -->

Code Example 4

<!-- a comment in html -->

Code Example 5

Insert a single-line, or multi-line comment. 
Comments are designated by the tags <! -- and -->

Use the comment function to hide scripts on unsupported browsers
. If you are programming in JavaScript or VBScript, 
you can use the comment function to hide the script on browsers 
that don't support it. Insert the comment at the start of the 
script, and end it with //--> to ensure that the script works 
on browsers that do support it.

Code Example 6

<!--This is a comment in html.-->
<!--You can put comments enywhere! It does not care if it is mid peice of
code in a peice of code! You must put the ending arrows in or it will
think everything is a comment! Note you can comment over multiple lines.
Use a ! at the start arrow, this may not make sence as the rest of
html uses tags where ! is at the ends.-->

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