Compounds. There are more carbon compounds than there are compounds of all other elements combined. The study of carbon compounds, both natural and synthetic, is called organic chemistry. Plastics, foods, textiles, and many other common substances contain carbon.
backplane is the shared capacity between interfaces on a switch switch fabric is also the shared capacity between interfaces on a switch and can also be the shared capacity between interfaces on multiple switches using some sort of interconnect, typically vendor specific.
Stackable switches can be interconnected using a special backplane cable that provides high-bandwidth throughput between the switches. Cisco introduced StackWise technology in one of its switch product lines. StackWise allows you to interconnect up to nine switches using fully redundant backplane connections. As you can see in the figure, switches are stacked one atop of the other, and cables connect the switches in daisy chain fashion.