The function of a CPU (Central Processing Unit) is to act as the brain of the computer by interpreting, processing, and executing instructions from computer programs. It carries out operations such as arithmetic calculations, logical operations, data movement, and control flow to manage the overall functioning of the computer system.

Main Functions of a CPU

• Fetching Instructions: The CPU retrieves instructions from the computer's memory in sequence.
• Decoding Instructions: The CPU interprets the instructions to understand the required action.
• Executing Instructions: It performs the necessary calculations, logical operations, or data manipulation.
• Managing Data: The CPU uses registers to temporarily store data and results of operations.
• Controlling Program Flow: It controls the sequence of execution, including decision-making through branching and jumps.

Components Supporting These Functions

• Control Unit (CU): Directs the operation of the processor by managing instruction flow and signals.
• Arithmetic Logic Unit (ALU): Performs arithmetic and logical operations.
• Registers and Cache: Provide fast storage to hold data and instructions during processing.

The CPU repeats the cycle of fetching, decoding, executing, and storing instructions very rapidly, enabling the computer to perform complex tasks efficiently.