(i) Metal - A metal is a material (an element, compound, or alloy) that has physical properties: hard, opaque, shiny, and conductivities. Metals are generally malleable, fusible and ductile. Metals are good conductors of heat & electricity.

Example: Aluminium, Copper, Iron, etc.

(ii) Non-Metal- Non-metals are opposite in properties of the metals. The non-metals are brittle, not malleable or ductile, poor conductors of both heat and electricity.

Example: Oxygen, Fluorine, Neon, Chlorine, etc.

(iii) Metalloids -  Metalloids are a type of semi-metals, that sometimes behave as a metal and sometimes behave as a non-metal.

Example: Silicon, Germanium etc.