A
metal (from
Greek μέταλλον
métallon, "mine, quarry, metal") is a material (an
element,
compound, or
alloy) that is typically hard, opaque, shiny, and has good
electrical and
thermal conductivity. Metals are generally
malleable — that is, they can be hammered or pressed permanently out of shape without breaking or cracking — as well as
fusible (able to be fused or melted) and
ductile (able to be drawn out into a thin wire). About 91 of the 118 elements in the
periodic table are metals, the others are
nonmetals or
metalloids. Some elements appear in both metallic and non-metallic forms.
