For introductory articles like this I also find it helpful to know that the whole positive / negative thing is arbitrary. In fact the assignment of "negative" t

For introductory articles like this I also find it helpful to know that the whole positive / negative thing is arbitrary. In fact the assignment of "negative" to electrons arise due to a mistaken interpretation by Benjamin Franklin of one of his experiments. So if you're wondering why gaining the primary mobile charge carrier makes things more negative blame Ben Franklin!