What are good conductors and define the bad conductors with examples?

good conductors are materials that can conduct electricity and heat efficiently. Most good conductors are metals but carbon (a non-metal element) also conducts electricity (pencil lead electrical switch experiment). Examples of good conductors are iron rods and copper wires.
on the other hand, bad conductors are materials/matter that can conduct heat and electricity partially or in most cases, doesn’t conduct heat and electricity at all. Bad (weak conductors) are usually non-metal and such as water (##H_2O##), plastic and paper. Although, there are some covalent molecules that conduct electricity in aqueous state such as aqueous hydrochloric acid, ##HCl## as there are free moving ions in the solution.