The main parts of a CPU:

• The CU can do the following tasks: It retrieves, decodes, and executes commands. It sends out control signals to hardware, and it transports data around the system.
• The ALU serves two primary purposes: It is capable of doing arithmetic and logical operations (decisions). The ALU is the place where calculations and judgments are made. It serves as a link between primary and secondary memory. The ALU is used to transport data between them.
• The CPU contains small pieces of high-speed memory called registers. The processor uses them to store little pieces of data that are required during processing, such as: the address of the next to be performed instruction
• Cache is a small quantity of high-speed random access memory (RAM) incorporated into the CPU directly. It is used to store data and instructions that are likely to be reused by the processor. This speeds up processing because the processor doesn't have to wait for data and instructions to be fetched from RAM.
• A bus is an internal high-speed link. Control signals and data are sent between the CPU and other components via buses.
• A clock is built into the CPU and is used to coordinate all of the computer's components. The clock emits a regular electrical pulse that synchronises (keeps) all of the components in time.

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