What distinguishes ‘skid marks’ from other types of tire markings?

Skid marks are specifically characterized by the indication that a vehicle's wheels have become locked and are sliding across a surface. This phenomenon occurs when a driver suddenly applies the brakes, causing the wheels to stop rotating while the vehicle continues to move forward. As a result, the tires do not maintain contact with the road in a manner that allows them to grip the surface, leading to a mark that reflects the friction between the locked tire and the pavement.

These marks differ from other tire markings, such as tire scrubs or yaw marks, which may occur under different circumstances, like when tires are still rotating or turning without being locked. While skid marks can vary in width and presence, their primary distinguishing factor lies in their connection to this locked wheel situation, making them a valuable piece of evidence in accident investigations to determine vehicle behavior leading up to a collision.