Tugboat

A tugboat or towboat is a type of boat that maneuvers other vessels by pushing or pulling them. This is done either by direct contact or by means of a tow line. Tugboats typically move vessels that are restricted in their ability to maneuver on their own, such as ships in a crowded harbor or a narrow canal,"How Pygmy Tugboats Dock a Giant Liner." Popular Science Monthly, March 1930, p. 22-23. Also, vessels that cannot move by themselves, such as barges, disabled ships, log rafts, or oil platforms. 

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Category:Boats