Tire

A tire, also spelled tyre, is a ring shaped component fitted around a wheel's rim to carry a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface the wheel travels over. Most tires, including those used on automobiles and bicycles, are pneumatically inflated structures that form a flexible cushion absorbing shock as the tire rolls over rough ground. A tire's contact patch, the footprint it presses onto the surface, is shaped to match the vehicle's weight and to spread the load without deforming the surface it rolls over.