Definition of kernel

The core of layered architecture that manages the most basic operations of the operating system and the computer’s processor. The kernel schedules different blocks of executing code, called threads, for the processor to keep it as busy as possible and coordinates multiple processors to optimize performance. The kernel also synchronizes activities among Executive-level subcomponents, such as I/O Manager and Process Manager, and handles hardware exceptions and other hardware-dependent functions. The kernel works closely with the hardware abstraction layer.

In C++ Accelerated Massive Parallelism (C++ AMP), a unit of computation on a data-parallel compute node.