CPU(central processing unit)
The CPU is the most processor is the most powerful component of a PC that performs all the actual work, that is, it executes stored program instructions as well as handles all instruction it receives from various hardware and software components. It is a highly complex, extensive set of electronic circuitry. The CPU is often referred to as a brain of the computer. The CPU follows a sequence: fetch, decode, execute, and store; that is, it fetches instructions from memory, decodes them into binary instructions, executes the action, and stores the output to memory.