Positive camber refers to the angle of a wheel rim that is mounted with the top side of the wheel angled away from the vehicle. Camber is the measurement of the inward or outward angle of wheels.
Camber is used to provide vehicle stability. On a low-slung sports car, there is almost always a negative camber, with the top edge of the rim inside the bottom edge, to help with cornering forces. On a higher-riding SUV or truck, positive cambers help maintain stability for a higher center of gravity. A wheel that is perpendicular to the driving surface with no tilt has zero camber.