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Bulldozers are used for moving, digging, and excavating large amounts of earth and soil. A large metal blade characterizes them on the front, moved by hydraulic arms and the tracks they run on, giving them traction with the ground. Some bulldozers come with rippers, an extended attachment in the rear resembling a claw that breaks up tough ground.
The three main types of bulldozers are crawler bulldozers, wheel bulldozers, and mini bulldozers: