The main difference between a ball bearing and a roller bearing is in the contact areas of the rolling elements. Rollers have linear contact while balls have point contact. Roller bearings, therefore, have higher radial load-carrying capacities, but usually operate at lower speeds due to greater friction caused by a larger contact area. This makes the roller bearing more suitable for use in heavy assemblies. These bearings can have either cylindrical or tapered rollers – each having its unique benefits over the other and are chosen depending upon application requirements.