A ball bearing is a type of rolling-element bearing that serves three main functions while it facilitates motion: it carries loads, reduces friction and positions moving machine parts. Ball bearings use balls to separate two “races,” or bearing rings, to reduce surface contact and friction across moving planes.
Some ball bearings are able to withstand a radial and axial load applied on the shaft, these combined axial/radial load bearings are achieved by axial angular contact.