They're boxes connected by tubes. Some boxes are bigger than others, depending on how much content they hold. Some tubes are bigger than others, too... that's why some sites are faster than others. And you gotta make sure the tube is thick enough, too. Otherwise, it bursts, and then the site goes down.
Seriously, though, the original manual didn't have any credits at all in it. I picked up the Uboat missions installer from one of the download suppliers, which didn't include a manual (at least, I didn't burn it on the same CD I burned the installer onto). I don't see a manual dumped in the SH4 directory, either.
So... no manual, no credits.
