1. Computer hardware is the physical parts or components of a computer, such as the monitor, mouse, keyboard, computer data storage, hard disk drive (HDD), system unit (graphic cards, sound cards, memory, motherboard and chips), and so on, all of which are physical objects that can be touched (that is, they are tangible).

In computer architecture, a bus (related to the Latin omnibus, meaning "for all") is a communication system that transfers data between components inside a computer, or between computers. This expression covers all related hardware components (wire, optical fiber, etc.) and software, including communication protocols.^[1]

Early computer buses were parallel electrical wires with multiple connections, but the term is now used for any physical arrangement that provides the same logical functionality as a parallel electrical bus. Modern computer buses can use both parallel and bit serial connections, and can be wired in either a multi drop (electrical parallel) or daisy chain topology, or connected by switched hubs, as in the case of USB.

1. An embedded system is a computer that has been built to solve only a few very specific problems and is not easily changed. In contrast, a general-purpose computer can do many different jobs, and can be changed at any time with new programs for new jobs.

1. A printed circuit board (PCB) mechanically supports and electrically connects electronic components using conductive tracks, pads and other features etched from copper sheets laminated onto a non-conductive substrate. PCBs can be single sided (one copper layer), double sided (two copper layers) or multi-layer.

The graphics components are the part of your computer that control and enhance how graphics (pictures, videos, programs, animation, 3D) are displayed on your computer screen.