Preventing a Website from Being Copied

Hello,

I'm in the process of putting up a website -- my first. There's a
number of tools (like WinHTTrack) that allow an entire site to be
copied to someone's hard drive to be examined at their leisure. Does
anyone know of a method to prevent tools like this from working? I
want people to visit my site, but I also want the stuff that's under
the hood to stay under the hood.

My thanks for all helpful answers.