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

Code Example 1

<!--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.-->

Code Example 2

<!-- a comment in html -->

Code Example 3

<!--this is comment-->

Code Example 4

<!--HTML Comment Example! HTML Comments do not affect your code in
any way, comments can be used to take notes to yourself, or if you 
are working with a team, this could be a good way to communicate 
without messing up any of your code. Comments will not be shown 
in your HTML webpage. -->

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 text is commented in html -->

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