Asphalt is a dark brown-to-black cement-like material obtained by petroleum refining and containing bitumens as the predominant component. Bitumen is a generic term for natural or manufactured black or dark-colored solid, semisolid, or viscous cementitious materials that are composed mainly of high-molecular weight hydrocarbons. The term includes tars and pitches derived from coal. Asphalt is used primarily for road construction and roofing materials due to its remarkable waterproofing and binding properties. The hard surfaces of roads, for example, depend on the ability of asphalt to cement together aggregates of stone and sand.
The first recorded use of asphalt as a road building material was in Babylon around 625 B.C., in the reign of King Naboppolassar. In ''A Century of Progress: The History of Hot Mix Asphalt'', author Hugh Gillespie notes that “an inscription on a brick records the paving of Procession Street in Babylon, which led from his palace to the north wall of the city, ‘with asphalt and burned brick.’”
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