There are 2 kinds of charge, called "positive"and "negative"charge -There is an attractive force between charges of opposite kind, a repulsive force between charges of the same kind Electric field (how interacts with environment) -Every charge alters the space around it, creating and electric field at every point -This electric field then exerts a force on other charges Colomb's law (Using it, what you can calculate, what does it tell us?) -The attractive and repulsive forces between two charged particles can be calculated from this law -Coulomb's law tells us how the force between charges depends on their charge and the distance between them