A bearing is a machine element that works with minimum friction by means of rolling elements (balls, rollers, etc.) between the inner and outer rings, and carries different loads according to its size and shape by making a rotary motion. Thus, as the material produces movement or work by rolling rather than sliding, the friction is minimized and less energy is used. Bearings can run horizontally or vertically and they are called radial or axial bearings based on that.
There are many uses of bearings in our lives. They are used in planes, metros, cars, buses, trains, motors, conveyor lines, dentists, skates, trucks, washing machines, microscopes, telescopes, wind farms, pumps, propellers, fans, elevators, ventilators, drums, and so on. Without bearings, the world stops.