Kernel

The central module of an operating system. It is the part of the operating system that loads first, and it remains in main memory. Because it stays in memory, it is important for the kernel to be as small as possible while still providing all the essential services required by other parts of the operating system and applications. Typically, the kernel is responsible for memory management, process and task management, and disk management.

This is a term for the computing elite, so proceed with caution. Today's operating systems are built in "layers". Each layer has different functions such as serial port access, disk access, and the user interface itself. The base layer, or the foundation of the operating system, is called a kernel. The kernel provides low-level services, such as the hardware-software interaction and memory management -- much like a kernel of corn. Or not.