CONDUCTORS AND INSULATORS

The substances that have an enormous amount of "free electrons" that can move through the material are called conductors. All metals are conductors, especially, noble metals such as platinum, gold or silver; however, their major drawback is the price. Due to their high price tag, we need to resort to other materials which also conduct electricity sufficiently well and which are more inexpensive such as copper and aluminum.

In the photo on your right you can see a copper wire (conductor) coated in plastic (insulator).

Materials that do not conduct electricity are called insulators; some examples of insulators are plastic, glass or wood. In these cases, electrons are strongly bonded to the nucleus.