Control bus address bus and a data bus line it is three

Are three buses, together referred to as the system bus.
A data bus (Data Bus): need to process sent back and forth between the CPU and RAM, or the need to store data.
An address bus (Address Bus): used to specify the address of data in RAM (Random Access Memory) storage.
A control bus (Control Bus): signals the microprocessor control unit (Control Unit) is transmitted to the peripheral device.

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