microkernel

A microkernel is a minimal computer operating system kernel which, in its purest form, provides no operating-system services at all, only the mechanisms needed to implement such services, such as low-level address space management, thread management, and inter-process communication (IPC). The microkernel is the only part of the system executing in a kernel mode. The actual operating-system services are provided by user-mode servers. These include device drivers, protocol stacks, file systems and user-interface code.
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<operating system> An approach to operating system design emphasising small modules that implement the basic features of the system kernel and can be flexibly configured.
(1999-08-02)