The system bus is a pathway composed of cables and connectors that carries data between the computer's microprocessor and main memory. It combines the functions of the data, address, and control buses to provide a communication path for data and control signals between the major computer system components. The system bus connects the processor to memory, storage, and input/output components to allow data transfer and coordination between devices.

1. The system bus
The system bus is a pathway composed of cables and connectors used to carry data
between a computer microprocessor and the main memory. The bus provides a
communication path for the data and control signals moving between the major
components of the computer system. The system bus works by combining the functions of
the three main buses: namely, the data, address and control buses. Each of the three buses
has its separate characteristics and responsibilities.
The computer system bus is the method by which data is communicated between all the
internal pieces of a computer. It connects the processor to the RAM, to the hard drive, to
the video processor, to the I/O drives, and to all the other components of the computer.
There are three types of buses in a computer, which all flow together. The data bus allows
data to flow between devices; the address bus tells devices where the data should go or is
coming from; and the control bus coordinates activity between various devices to prevent
data collisions. “Collisions” is a term that identifies the corruption of data resulting from
simultaneous use of the data and/or address bus.
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North Carolina State University is a public land-grant research university in
Raleigh, North Carolina. Founded in 1887 and part of the University of North
Carolina system, it is the largest university in the Carolinas. Wikipedia
https://e115.engr.ncsu.edu/hardware/system-bus/
Question: What does system bus made up? Or What is the purpose of systembus?