I was wondering if I could develop a comment section where people would post comments without using php or asp. The only thing that i would like to use ih javascript, html, css, ajax and things like that. Is this achievable without the usage of php or asp?

No. A comment system needs some kind of storage on the server, so some scripting is required.

Yes but your javascript would include Ajax so that you can send the comments back to the web server for server side processing.

There's already a service (among a few) that do this. Take a look at Disqus.

You implement it on your site by including a block of javascript they provide.

If you do this on your own, again..you can develop the javascript code to send the comments for processing.

If you notice that on Daniweb, when you submit a reply to a post, there is no post back. I'm assuming there's javascript/Ajax handling the process.