Axle refers to a beam supporting a vehicle on which one or more wheels turn. Axles also house and support the differential, shafts, and wheels that propel the vehicle.

Axles can be conveying power to turn the wheels, or merely supporting the vehicle's weight and allowing the wheels to turn. Axles are designed to suit a variety of suspension systems. Beam axles are traditional, but many vehicles now utilize axle assemblies for independent suspension systems.
There are types of axles:
Types of Axles
1. Straight axle
2. Split axle
3. Tandem axle