The wheels on the bus go round and round

The Bus-System (short for Binary Unit System) is the part of the compute that relays data from one component to another. This commonly happens through separat channel, one for instructions, data, and addresses. This separation through specific channel helps with throughput and mitigates the Von-Neumann bottleneck, by allowing different sets of data to be transmitted in parallel.

Bridges and I/O

The CPU does not communicate directly with slow devices in general, instead only communicating with a bridge that is connected to a secondary bus system. The bridge is responsible for handling the communication with these slow devices. This layer of indirection keeps the main bus from getting clogged by slow I/O operations.