To determine a vehicle's wheel alignment specifications a technician uses three terms: camber, cast and toe-in. Broadly speaking, camber relates to the angle measurement of the wheel as seen from the front; caster represents the steering angle and pivot of the tires; and toe-in refers to the distance between tires.
Camber, caster and toe-in are the three most commonly used terms for determining wheel alignment as of 2015. The perfect wheel camber angle is between positive and negative camber. Positive camber, as seen from the front of the vehicle, refers to the wheels being pushed outward at the top and away from the wheel wells. Negative camber features an inward tilt, toward the wheel wells. Too much negative or positive camber leads to tire damage.
Ideal caster positioning is positive due to the benefits it confers to handling and stability. Caster stems from the steering, or pivot point, within the suspension system of a vehicle and is considered positive if the point is angled forward. Conversely, negative caster means the pivot point is angled backward. Toe-in refers to how parallel the front and rear tires are to one another. Also, toe-in means that the two front tires are tilted toward one another.