The pieces of equipment which are attached to the CPU of a computer and which it can access are called.
The pieces of equipment which are attached to the CPU of a computer and which it can access are called peripherals.
A peripheral device is defined as a computer device, such as a keyboard or printer, that is not part of the essential computer (i.e., the memory and microprocessor). These auxiliary devices are intended to be connected to the computer and used.
Motherboard. The motherboard is the main component of a computer. It is a board with integrated circuitry that connects the other parts of the computer including the CPU, the RAM, the disk drives (CD, DVD, hard disk, or any others) as well as any peripherals connected via the ports or the expansion slots.