A Harbor Work Boat is a type of vessel that is used to perform various tasks in and around harbors. The most common type of Harbor Work Boat is the TUG, which is a powerful boat that is used to pull or push other vessels, such as barges, ships, and boats. Tugs are also used to maneuver vessels in tight spaces, such as docks and marinas. They are also used for towing, salvage operations, and firefighting.