Those are files you won't find on CD, but which may be
useful for some people.
Untouched kernel ELF, same as one needed by normal yaboot.
Small initrd which tries to find ppcrcd.sqf and mount it
(optionally copying it to ram).
Bootable kernel images with initrd included
Image bootable from firmware on CHRP machines (Pegasos).
Same as above, but with note added, for RS6000. This one is
used on CD as /boot/vmlinuz.
Kernel bootable from OldWorld Macs' OpenFirmware.
Kernel which may be booted using miBoot or BootX (Mac OS).
Kernel bootable on NewWorld Macs.
Kernel bootable on broken prep machines.
Kernel bootable on PREP machines.