В

of Operation

Prior to the 19th century and extending into the early 20th century, heavy machinery was operated using human or animal power. However, the introduction of portable steam-powered engines led to the modification of these machines with the new engines, such as the combine harvester.

The design of a central tractor was adapted to incorporate the new steam power source, resulting in the development of the steam tractor and steamroller

In the 20th century, internal-combustion engines became the primary power source for heavy equipment. While kerosene and ethanol engines were initially utilized, diesel engines have now become dominant. Hydraulic machinery largely replaced mechanical transmission in many cases

Electric-powered machines, such as forklifts, emerged in the early 20th century. The Fordson tractor, produced by Caterpillar Inc., was the first mass-produced heavy machine in 1917