Comments are great! Comments can help explain your work to other coders and even to your future self.
Comments do not get shown in the actual webpage. Although your comments can contain anything you want, yet it is recommended that you keep them precise and helpful.
For writing a comment use the syntax: <!-- text -->
If you feel your HTML is a bit confusing to read, just put in a comment there as shown above. This way, when you come back to the code after some time, things will still make sense.