Bitumen is a highly viscous, black, organic liquid that is obtained from crude oil. It is the sticky residue left when all of the lighter components of crude oil have been removed during the distillation process. It is similar to tar, which is a residue obtained during the distillation of coal.

Bitumen was once commonly used as a waterproofing sealant in boats and in building construction, but its principle use now is as a binding agent mixed with mineral aggregate for paving roads.