Define bitumen and tar

Bitumen is a black or dark brown, sticky, waterproof mixture of hydrocarbons, obtained as the residue after distillation of crude petroleum or found as natural deposits. It is soluble in carbon disulphide and is used as a binder and waterproofing material in roads and roofs.

Tar is a dark brown to black viscous liquid obtained by destructive distillation of coal, wood or peat in the absence of air. It is used for road surface dressing, priming, and as a preservative for timber and pipes. It is more temperature-sensitive and less durable than bitumen.