<< certainly better than IIS! No seriously, it all depends on what kind of content you're serving. Apache uses the fork() method of handling incoming connections; that is, one httpd process per connection. These take some time to time out and can sometimes run out of control. IIS uses a single multithreaded process to handle all incoming connections. Both models have their advantages; I find apache more flexible, less swiss-cheesish and much faster for my own use, YMMV! >>
I don't use Apache for Win32, but I was under the impression that on Win32, Apache uses native threads. Context switching in the NT kernel is massively expensive.
Under Unix, fork() was largely implemented for reliability reasons, and I think the results speak for themselves.