Yaird generates initial boot images in initramfs format.

the boot image is an intermediate step between the boot loader (eg. grub, lilo) and the init scripts on the root file system; it loads modules and enables devices to a level where the kernel can access the real root file system, and then hands over control to the init scripts.

main features:
- strict build logic: less risk of producing non-booting ramdisks
- small ramdisks: optimized for the currently running system
main shortcomings:
- no automatic firmware loading (some scsi drivers needs manual work)
- limited support for encrypted disks (enable manually in config)
- produced ramdisks cannot boot into a different system setup!
yaird is good for stable systems, like servers (especially if managed remotely) and embedded systems.

if you need a flexible ramdisk tool, then use initramfs-tools instead.

see http://wiki.debian.org/initrdreplacementoptions for status and comparison with other ramdisk tools.