Metals: generally shiny, malleable, and hard. They are good conductors of electricity.
Non-metal: do not conduct heat or electricity very well. Are typically brittle and are not easily mold into shapes.
Metalloids: share characteristics of both metals and non-metals and are also called semimetals. Metalloids are typically semi-conductors, which means that they both insulate and conduct electricity. This semi-conducting property makes Metalloids very useful as a computer chip material.