It depends on your perspective. If you're building an application that passes disjointed components around, then yes, you can combine the three (js,html,css) in

It depends on your perspective. If you're building an application that passes disjointed components around, then yes, you can combine the three (js,html,css) into a self reliant container. If you're building a website that is basically a series of pages, that is part of a book per say, then it doesn't quite make sense. I would say 10 years ago it was not common to think of the web as a platform. Over the last 5 years using the dom as platform and js as the source code has become much more predominant. Whether the scope of your business can be used by this architecture would determine whether it would come up in your day to day.