Resistance is measured in ohms. We use resistance to control electrical flow. Things that slow down, or prevent electricity from flowing to some place to some where are called resistors or insulators.
Electrical conductors have a relatively low resistance rating, and are useful for moving electricity to one place, to another. Most metals like copper and aluminium are good conductors. Gold and platinum are excellent conductors.
Water is a very good conductor, which is why electricity and water is not a good mix. Which also makes the human body an excellent conductor.
When we want to stop the flow of electricity, or keep it contained. We use things called insulators like air, glass, wood, rubber, and most plastics are good insulators.