A tapered roller bearing is a bearing that has been designed to support a rotating shaft that is tapered. The bearing consists of two main parts: the inner ring and the outer ring. The inner ring is made up of a series of rollers that are spaced evenly around the circumference of the ring. The outer ring is made up of a series of raceways that are equally spaced around the circumference of the ring. The rollers are free to rotate within the inner ring, but they are constrained by the raceways in the outer ring. As the shaft rotates, the rollers roll along the raceways and provide support for the shaft.