Yes, you can dynamically add comments to the DOM.

A collection of JavaScript reference articles. I’d recommend John Resig’s Learning Advanced Javascript and Addy Osmani’s Essential JavaScript Design Patterns for Beginners. Mozilla has been doing a phenomenal job of documenting the core technologies behind the web. In the past year alone, they have produced the essential go-to reference for JavaScript. w3schools no more! They have almost done too good of a job, as I had the darndest time re-finding this page. It appears in the Learning section, completely separate from the Docs section.