(1) The foundation part of an operating system that is designed for the hardware it runs in. The other components of the OS interact with the microkernel in a message-based relationship and do not have to be rewritten if the OS is ported to new hardware. Only the hardware-dependent microkernel must be reprogrammed. Contrast with
monolithic kernel. See
kernel.
(2) A small control program designed to perform a limited set of functions in one hardware platform.