The system unit is the main body of the computer. It contains different components that are enclosed in a rectangular casing.The casing is avalable in two different shapes:
i. Horizontal shape: It is called desktop casing ii. Vertical shape: It is called tower shaping.
The most important compnent of the system unit is known as motherboard. It is a rectangular circuit board. It is made of silicon. All the components of the computer are connected to the motherboard. An electronic pathway on the motherboard connects different components of system units with each other.The main componnts in system units are microprocessor, Ram, Hard disk drive, Floppy disk drive, CD Drive.