The term 'Harbor Hauler' refers to three different types of vessels: a SCOW, a TUG, and a garbage SCOW. A SCOW is a flat-bottomed boat with a blunt bow and a square stern, used for carrying cargo or dredging. A TUG is a powerful boat designed to maneuver other vessels by pushing or pulling them. A garbage SCOW is a vessel used to transport garbage from one location to another. All three of these vessels are used in harbors to haul goods, materials, and waste.