A microkernel is a minimalistic approach to operating system design that focuses on providing only the essential services needed for the system to function. This includes basic functions like managing memory, processes, and communication between different software components. By keeping the core of the operating system small, it aims to improve stability and security, as fewer components mean fewer potential vulnerabilities. In a microkernel architecture, additional services, such as device drivers and file systems, run in user space rather than in the kernel space. This separation allows for greater flexibility and easier updates, as these services can be modified or replaced without affecting the core kernel. Examples of microkernel systems include Mach and QNX.