state the main difference between a between a conductor and an insulator?

Dear student
Differences between a conductor and insulator

1. A conductor allows flow of electric current through it when a potential difference is applied across its ends while an insulator does not conduct electricity unless vert very high potential difference is applied across its ends.

2. A good conductor of electricity is generally a good conductor of heat, insulators do not conduct heat too.

3. Conductors have free electrons on its surface, insulators have bounded electrons on its surface.

Example of conductor: Silver (Ag), Copper (Cu), Aluminum (Al)

Examples of insulators: Ebonite, Sulphur, Poly-vinyl Chloride.  

Regards