What is the bearing?
The bearing is a support on which the neck ("thorn") of a shaft or axis lies.
the Bearing is made usually of two bolted parts in which inserts with deepenings for a shaft are located. It gives the chance in process of deleting of a surface of inserts and a shaft to pull together parts of the bearing.
Inserts for reduction of friction are made usually of antifrictional alloy, in them make flutes for a channel of lubricant oil.
Wide circulation have so-called ball bearings in which the shaft rotates in a ring from the small steel balls placed in a round holder. At rotation of a shaft each ball freely rotates round its pivot-center, than resistance from friction considerably decreases.