@SQUEEKY2 is correct. Up until recent years, nearly every piece of heavy earth moving equipment used in the US came out of Caterpillar Corporation. They started by making steam tractors in the 1890s. The traction innovation of using tracks instead of tires caused a company man to remark that the machine moved like a caterpillar, thus the name.
Starting in the 1920’s, Caterpillar moved from the farm into highway development, and their machines were prominent in later projects such as the Hoover Dam and the TVA. Their most popular product by far was their deisel-powered bulldozer, popularly known as the “cat.” The highly skilled men who operated the famous caterpillar-yellow cats were honored with the title “catskinner.”
Caterpillar Corporation is traded on the NYSE as CAT.