Question

I was wondering if it’s possible at all to do something like the following:

Let the website examine whether a visitor has Javascript enabled or not. If not a pop-up will appear telling them to enable JavaScript for a better website view.

It doesn’t have to be a pop-up, it could be anything, really.

Is it even possible to do something like that without using JavaScript?

In the worst case scenario I just leave a plain text note in my footer or so.

Answer 1

Anything inside a <noscript> block will only be shown to people with JavaScript disabled or unavailable:

<noscript>
  Please enable JavaScript to see the awesomeness
</noscript>