Booting a computer is always more complex than one wants to think. On the PC side, it looks as if BIOS finally is retired and replaced by EFI (I wonder which was the last OS to use BIOS for anything that just loading a secondary bootloader). On Mac, EFI has been around for a while. On embedded Linux systems, however, u-boot has been a big player for a long time.
Read more at Linux Journal
