After installing XAMPP on a couple of my XP boxes and getting a few 'extras' to work (like YaBB and WordPress), I decided it was time to see what was happening under the hood. A simple way is to watch what is happening is to use Task Manager.
Well, what's this? There are TWO instances of httpd.exe (the Apache daemon) running in memory. This was bugging me a bit (I am the nuts and bolts type). Google helped me out some. It turns out that Apache 2.2 uses the MPM (multi-process module) as the default on Windows, and the initial load also creates a single child process. (this is true on Windows -- with the build provided with XAMPP) I can't speak for the other OS variants of XAMPP. As far as I can tell (by some testing), only one child process will be created in this environment.
This one is the right info: