K is for (Computing) Kernels
A kernel is the main component of an operating system and basically controls everything that occurs in the computer system. When you turn your computer on in the mornings, the kernel is the first element that will load into the memory and stays there for the complete duration of your computer session.
A kernel has many duties within a operating system by mananging the jobs of the computer and the computer hardware. The kernel is responsible for the allocation of memory that allows computer software to run. Multiple programs running at the same time will fight for the memory and the kernel will decide how much memory can be used per computer program and if it needs to allocate for more memory. The kernel can tell if a faulty program is trying to interfere with operational programs and will correct this from happening. It enables the CPU to be able to multitask by how many jobs are out there to run at one time. If a program needs to use the network driver or other hardware, it recognizes this and provides this capability. A kernal does it all and if your computer crashes it really means that the kernel crashed.