A material which allows electric charges to move freely. A material that prevents charge from moving freely. When I think of Electricity, the first thing that I think of is that magical juice that comes into my house. However, I also think of electricity whenever I get out of my car in this dry Minnesota air. It may not be surprising to many of you, but these two things are essentially the same thing.
Electricity is the movement of charge back and forth.
It is this moving charge that keeps your TV running and gets your attention on those dry winter days. For those of you who have never rubbed a balloon on your head when you were kids, I will try to explain it to you. We should really try to figure out what this charge stuff is. This is an extremely deep question. Physicists only really convinced themselves that they had the answer to this question in the 40's.