The basic function of any ball bearing is to reduce friction between the two elements because rolling things have less friction than the sliding things and the reason is not hard to fathom. If things were to slide instead of roll the entire surface of the two things sliding against each other would be in touch which means more friction and more resistance.

When things are rolling they have less friction because of the fact that they have less amount of surface in contact and that means that less friction and resistances.

The bearings then actually have an inner surface to roll over and outer surface to roll over. These balls then get most of the load and but of course then there are various kind of ball bearings for different applications.

Roller ball bearings have three components namely the outer race and the inner race. Balls get the load from the outer race and transfer the load to the inner race. But roller ball bearings can only handle small amounts of load since the balls have less area of contact to the races.

Roller bearings are a variety of ball bearings in the sense they do not have the balls but a cylinder where the bearings come in contact over a large area and that means that they can in fact handle larger loads. The variety used in cars is the tapered roller bearings and that means that they can in fact handle larger loads and also they are used in pairs so that the load can be handled in both the directions.

Nowadays a lot of ceramic ball bearings are being used since they are lighter than steel and generate less heat and hence can go faster than steel. The ceramic material can be silicon nitride or silicon carbide or zirconium.

Again you can have entire ball bearing built out of ceramic material or you can have only the balls of the bearings built of ceramic.

There are two types of ceramic bearing i.e hybrid ceramic ball bearings and Full Ceramic Bearing. The hybrid ceramic bearing have a steel inner and the outer rings are formed with ceramic balls whereas in case of full ceramic bearing the inner and the outer rings and the balls are made of ceramic only. There are many kinds of ceramic materials, the most common ceramic materials are Si3N4 which is defined as the silicon nitride ceramic material and is black in color. The other kind of ceramic material is known as the silicon carbide material or SiC and is also black in color. The zirconium dioxide or ZrO2 is also known as zirconia or zirconium oxide, they are white in color, this ZrO2 or zirconia ball looks exactly like a pearl. It has been known that the ceramic material is not stronger than a steel, but ceramic bearing are lighter and have lower friction than that found in a steel which makes ceramic bearing go faster with lower heat generated. More then a decade the ceramic ball bearings have been used for cutting tools, turbines, satellites and even in formula 1 racing.

Few of the most important component of the ceramic ball bearings are:

1. Thermal Expansion: On of the utmost feature of the ceramic is that it  expands and contracts with changes in temperature which is like 35% less than steel, thus allowing the cyclist with less amount of vibration and offers smoother motion.

2 . Less Conductivity: The Ceramics are electrically NON-conductive, and chemically inert, thus do not suffer from oxidation and the rust that degrades the surface of a traditional steel ball bearing.

3. Weight Reduction: Silicon nitride ceramic balls are only about 40% of the weight of steel ball bearing which means that less weight equals to less rotating mass, making high speed, acceleration and deceleration possible with less effort.

4. Modulus of Elasticity: Ceramic is 50% harder, which allows it to takes more amount of work to alter its original shape and size.

The ceramic balls bearings weigh up to 40% less than steel bearing balls simply depending upon the size thus reducing the centrifugal loading and skidding which means that the hybrid ceramic bearings can operate 20% to 40% faster than conventional bearings. This reduction in force reduces the friction and the lighter ball allows the bearing to spin faster, and uses less energy to maintain its speed.