United Rentals is the largest equipment rental company in North America, renting construction and industrial equipment like excavators, generators and aerial lifts to contractors, industrial companies and event organizers rather than selling equipment outright. Renting lets customers access expensive machinery for specific projects without tying up capital in equipment they'd only use occasionally, a value proposition that has driven a long-term shift from equipment ownership toward rental across the construction industry. The company has grown substantially through acquisitions of smaller regional rental companies, building the scale and branch network needed to serve large national contractors across many markets. United Rentals' revenue is closely tied to construction and industrial activity levels, so its results tend to track broader economic cycles, though rental penetration growth has provided a tailwind on top of that cyclicality.