Caster (Video clip - Choice of download speeds Broadband (150k+) or Dial-Up (28k or 56k))

What is Caster
Caster is the forward or rearward tilt of the steering axis, in reference to the vertical when viewed from the vehicle side.
Positive caster is where the steering axis is sloped towards the rear.
Negative caster (not common) is where the steering axis is sloped towards the front.

Why
High positive caster makes the steering heavier but results in the car remaining better in a straight line at speed. Shopping cars, Renault 5, Ford Fiesta, etc have caster values close to zero. BMW 7 series or Mercedes 500 have high positive caster to assist in keeping straight on the autobahn!

Cross Caster
Cross caster is a difference in caster from side to side. As a rule of thumb a car will steer toward the side with the least caster.