camber is just the angle of the tire relative to the road surface. If the tire is standing straight up, that's zero camber, if it leans in toward the car, that's negative camber, and if it leans out, that's positive camber. It is an ironic twist of language that negative camber is what you want, and positive camber is what you should avoid at all costs.

you want a camber curve that keeps the tire straight up and down when you are driving straight, and leans the tire in slightly (1 to 2 degrees of negative camber) during cornering. this goal is nearly impossible to meet, but some suspensions do come close.