The motherboard is the main circuit board inside your computer. It is the largest and most complicated piece of equipment within a computer case. It houses the central processing unit (CPU) the BIOS, the chipset, the system bus and main memory (RAM and ROM) Located on the motherboard are also expansion slots for adding devices and power connections. All of the peripheral devices on a computer are installed directly on the motherboard or are linked to it by a cable connection. The main purpose of the motherboard is to coordinate all the individual processes of each component so they all work properly together. The main system board is what processes input from a computer user and produces output which is seen on the computer screen.