Of the four discs that come in the Mac OS X Server package, only one will appear on the desktop in Mac OS 8. This is the main install disc. It appears because it has both a Mac OS Extended format (HFS Plus) partition and a UFS format partition on it. The other three discs contain only UFS partitions and will only be available while in Mac OS X Server.
Mac OS X Server disc (contains both UFS and HFS Plus partition)
NetBoot disc (contains only UFS partition)
WebObjects disc (contains only UFS partition)
Solutions disc (contains only UFS partition)