The system unit is typically connected to several peripheral devices, including input devices like a keyboard and mouse, and output devices such as a monitor and printer. It may also connect to storage devices like external hard drives and USB flash drives. Additionally, networking equipment like routers and modems can be linked to the system unit for internet access. These devices enhance the functionality and usability of the computer system.
BUSEach channel, called a bus, allows the various devices both inside and attached to the system unit to communicate with each other
BUSEach channel, called a bus, allows the various devices both inside and attached to the system unit to communicate with each other
That sounds like you are asking about device driver software.
On the system unit by a connector on a cable
The five components of a computer:input devices, output devices,system unit,storage devices,and communications devices.
system unit
Bus
BIOS
BIOS
Assuming that when you say system unit of a computer you mean the computer case A.K.A. the tower, then no, hard drives are not always installed internally. Hard drives can be in external enclosures, hard drive docks, and even network attached devices.
Input Unit of the computer system consists of the input devices. following are the devices included in the input unit. i.e Keyboard, Mouse, Scanner, Microphone.(By Mansoor Abid MCS (Pakistan))
basic input output system (BIOS)