Bogie is a set of wheels fitted under a railcar or a locomotive. Bogie is classified as a one-axle, two-axle, three-axle or et cetera, depending on the length of the railcar. The one-axle is a two-wheel bogie; two-axle is a four-wheel bogie and so on.
The primary function of the bogie is to give support to the railcar body; to provide stability in curved and straight tracks; to provide smooth ride through the absorption of vibration.
This is a set of wheels fitted under a railcar or a locomotive for transporting goods or people.