Definition: CPU

(Central Processing Unit) The computing part of the computer. Also called a "processor" and "microprocessor," the CPU comprises a control unit that executes the instructions in memory and an arithmetic logic unit (ALU) that processes (calculates, compares and copies) the data in memory.

Today, the CPUs in most computers are contained on a single chip, and except for CPUs in appliances, they have many processing cores that simultaneously perform operations (see multicore). See microprocessor, control unit and ALU.

CPU, Computer and Computer System
The CPU, clock and main memory make up a computer. A complete computer system includes input/output channels, storage and an operating system. In practice, the terms "computer" and "computer system" are synonymous.

GPUs and NPUs
The GPU was designed for graphics and is used for AI, while AI accelerators such as the NPU (neural processing unit) are designed for AI only. Although NVIDIA is known for its GPUs, Google, AMD and Amazon also make AI chips, each with different quantities of mathematical processing cores. See CUDA core, Tensor core, AMD Instinct and Amazon AI chips.

Computer Chips

These are the chips used in today's computing devices. The flag postage stamp on the CPU represents the area the actual transistors take up, except that the stamp is much thicker! For AI, the GPU and NPU execute mathematical calculations in parallel (see GPU and neural processing unit).