Here's why:

* Insulators are materials that resist the flow of electric current. This is because their electrons are tightly bound to their atoms and are not easily freed to move.

* Conductors, on the other hand, have electrons that are loosely bound and can move freely, allowing for easy flow of electricity.

Some examples of insulators include:

* Rubber

* Glass

* Plastic

* Wood

* Air

Let me know if you'd like more details about conductors and insulators!