Electricity is the energy from the flow of electrons.
Conductors are materials that freely allow the flow of electrons with very little resistance.
Semiconductors are materials that do not allow electors to flow freely but do not directly stop them either.
Insulators are materials that greatly impede or stop the flow of electrons with very high resistance.
EXAMPLE OF CONDUCTOR - copper
EXAMPLE OF SEMICONDUCTOR - silicon (used in computer chips)
EXAMPLE OF INSULATOR - rubber