Metals- A metal is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically malleable or ductile. (*An example of a metal is iron.) Non-metals- A nonmetal is a chemical element that mostly lacks the characteristics of a metal. Physically, a nonmetal tends to have a relatively low melting point, boiling point, and density. A nonmetal is typically brittle when solid and usually has poor thermal conductivity and electrical conductivity. (*An example of a non-metal is Oxygen.) Metalloids- A metalloid is an element that has properties that are intermediate between those of metals and nonmetals. Metalloids can also be called semimetals. (*An example of metalloids is Silicon.)