System unit definition
A system unit is the main box-like structure of a computer with all the essential components needed for the computer to work. Inside the system unit, you'll find the brain of the computer called the CPU (or central processing unit), the main circuit board (known as the motherboard), and RAM (random access memory).
It's like the “body” of the computer that houses all the important parts that allow it to function and perform tasks. The term is generally used to differentiate between the computer and its accessories (e.g., keyboard, mouse, or monitor).
See also: analog computer
What does a system unit do?
- Protection. The system unit shields internal components from damage, dust, and debris, making sure the computer can run reliably.
- Organization. The system unit is designed with compartments to neatly arrange the CPU, motherboard, memory, and storage.
- Communication. Components within the unit exchange data using the motherboard's circuitry and connectors.
- Power distribution. The system unit also houses the power supply (PSU) and converts outlet power for the computer’s components (e.g., CPU).
- Cooling. Many units have fans and heat sinks to dissipate the heat generated by the components. The system unit prevents the computer from overheating.
- Expansion. The system unit's slots allow users to add extra hardware components (like graphics, sound, or network cards) to customize their machine.
- Interface. The unit offers ports to connect peripherals like monitors, keyboards, and USB devices.