Burgejos000 on "How to display information on a page"

Thanks for the reply. I am using the Graphene theme. What i am basicly doing is making a directory type plugin. Users will be able to search a database by choosing selecting information from a search bar via javascript. once they click submit, a php file will execute, collect the specific data from the database and send it back to the javascript to display the information on a page. Im using the same idea as this guy here: http://teamtutorials.com/web-development-tutorials/pulling-drop-down-values-from-a-database-using-javascript-and-php
Just as an example, as i a a newbie to all of this, what would an example of an HTML comment look like?
I know that i can use the echo tag to display information via php. Although it would be very useful information to know how to display java and html through php considering the plug in I am trying to make.
I have explored many options with this. I originally wasn't planning on making a plugin. I tried entering some code through the text field on the edit page, page. I tried creating a child theme, but whenever i copy and past the graphene theme, rename it graphene-child, and activate it, the layout is messed up and isnt as it should be. I'v created a custom template, but when doing that, i can't display javascript, or execute another script without interrupting the loop.php So i just thought it would be easiest to create a plugin because it should be able to execute other scripts in the plugin folder without a problem, correct? I think this would be the most efficient way to do it, correct?
But again, back to the main question for this reply, how would i add an HTML comment and allow it to be displayed in a php script?