How was Rockefeller and monopoly different from Carnegie and?

John D. Rockefeller and Andrew Carnegie both wielded immense power in their respective industries, but their approaches to monopoly differed significantly. Rockefeller, through Standard Oil, perfected horizontal integration, controlling nearly all oil refining in the U.S. and effectively eliminating competition. In contrast, Carnegie, with his steel empire, utilized vertical integration, owning every aspect of production from raw materials to distribution. While Rockefeller's focus was on consolidating market power through aggressive tactics, Carnegie emphasized efficiency and innovation within his supply chain.