Roller bearings are a particular type of bearing that use rolling elements to support loads and reduce friction. Vis-a-visball bearings, roller bearings have barrel-shaped rolling elements instead of spherical balls. They can withstand heavier loads than similar size ball bearings but cannot handle as high speed as ball bearings.
Roller bearings contain an inner and outer ring that house the rollers and bearing cage. The cage, also called the retainer maintains spacing between rollers and holds the roller elements together.
The four primary types of roller bearings used in varying applications each with different designs are cylindrical, spherical, tapered, and needle roller bearing.