Comments text on html

Realy need more enlightment on it. thanks

Comments are texts that you put in the code to explain something or to enhance the readability of the code.
They are useful for humans (a present you, a future you looking back at your code or whoever else will come in contact with your code) but they are completely ignored by the machine.
The comments in HTML will not be rendered in a web browser (but they will still be available in the source code, that you can inspect with the developer console of your browser - press F12 for this).

A comment in html is any text enclosed between <!-- and -->
Example:

<!-- I am a nice piece of comment, am I not? -->
<p>I am not inside a comment, so I get rendered by a web browser</p>