A tugboat or tug is a marine vessel that manoeuvres other vessels by pushing or pulling them, with direct contact or a tow line.

Why do tugboats push instead of pull?

Q. Why do I see so many tugboats pushing barges rather than towing them? A. In terms of power and water resistance, it is more efficient to push rather than pull a barge.

How does a tugboat pull a big ship?

How do they move large ships? Depending on the size of the ship and the tugs, once in port, one or more tugs can tow via a tow line or push the ship into dock. ... With indirect towing, the tug can act as a rudder and pull the ship to one side, helping rotate the ship as it moves.