[Techtalk] Using a web browser to control stuff locally

[esme]

Hello!

Apologies if this might be off-topic here -if so, please just point me to 
where I should be posting this.

How do you invoke a shell command from a web page?

I want to create a web page that will provide buttons that can be clicked 
allowing me to select from a number of my CDs that I've ripped from HD.

I  actually managed to do this kind of thing some years ago on my old Amiga, 
but using an extended form of the Amigaguide ML called iXG.  I'm sure I can 
manage the visible side of the HTML page (iXG wasn't too dissimilar to HTML), 
but what I don't know is how to do the bit where you invoke a program (like 
amarok, or some other audio player) with the necessary parameters (which 
files to play) so that the page acts as a front-end to the player.

Thanks!

Esme  (PS: if it makes any difference, I use KDE for preference - but can 
happily use Gnome or IceWM or whatever for this, if need be. )