A bus is a route of communication that transfer data between various components of a computer system, such as the processor, memory, and peripherals.

The three primary types of buses in a microprocessor are:

• Address Bus: The address bus is used to transfer memory addresses between the processor and memory. It is responsible for carrying the location of the data that needs to be accessed or modified. 
• Data Bus: The data bus is used to transfer data between the processor and memory or input/output devices. It carries the actual data that is being read from or written to memory or an I/O device.
• Control Bus: The control bus is used to carry control signals between the processor and various other parts of the computer system, including memory and input/output devices. It carries signals that control the data transfer between these components, including signals to start and stop data transfer, as well as signals that indicate the type of operation being performed.