The tread on a car tire is the part of the tire that contacts the road directly. Inferior or worn tire tread severely impacts how well a car handles and steers. Tire tread provides the traction necessary for a driver to be in control of a car as it is driven. Without adequate traction, a car will slip, slide, or be uncontrollable. Tire tread is designed to dig into the roadway surface and repel water and other liquids away from the main contact surface of a tire.
The tread design on a car's tires has a radical impact on its handling abilities. Car tires come in a variety of different tread designs, from tires designed for highway/city driving to tires designed for off-road or recreational types of driving. Car tires that have deep ridges and fissures in their tread will provide excellent traction and stability; car tires with more streamlined and symetrical tread designs will ride smoother and quieter at highway speeds, but they won't offer as much traction.
Car tires that have virtually no tread left on them are considered to be bald tires. Driving a car on bald tires is very dangerous, as the minimal or non-existent tread patterns on the these types of tires provide virtually no traction at all. The slightest bit of grease, oil, or even water on a roadway could cause a car driven on bald tires to spin out of control. All car tires come with tread-wear indicators, which are small rubber notches machined into the grooves of a tire that indicate when the tread is sufficiently worn to merit tire replacement.
