Leave unseen mark?

[MarkFoster]

Can I leave a mark in a code that will be unseen. Like on a custom HTML page. Lets say I want to know where certain parts are. Is there a custom code I can put in for example "----Names Here-----" but working without being seen?

[Spank]

You can comment a line out in html like this:

<!-- Names Here -->

I hope that's what you mean(?)