Concrete is one of those technologies that was used for centuries—in this case, by the Romans—and then had to be invented again centuries later. But once we rediscovered it, we were hooked. The only thing that humans consume more of, by volume, than water is cement, concrete's key ingredient. We use so much of the stuff that the cement industry is responsible, all on its own, for 5 percent of global carbon dioxide emissions.

Source: http://m.theatlantic.com/technology/arch...