Tugboats have inspired many hardworking cartoon and storybook characters throughout the years. Real-life tugboats are as tenacious and full of character as their cartoon counterparts, and tugboat crews are often the salty sailors of legend. These stout little boats range from the 50 foot harbor or yard tug to the 250 foot long off-shore anchor harboring tugs. Tugboats generally perform one of three tasks. The first is known to those in the industry as a "ship assist," as in assisting larger ships in and out of harbors and ports. Tugboats also tow ships and barges which are not under their own power, and aid in construction work taking place on or near a body of water.

Today's ships are vastly larger than they have ever been throughout history. These huge ships can move forward and backwards easily, but are usually unable to maneuver sideways. Some ships, have transverse bow thrusters which can assist the ship to move sideways, but even these advanced designs only allow limited side to side mobility, and many ships still require what is known as a "tug assist."

In a tug assist, one or two tugboats meet the larger ship while it is still outside the port. A common scenario has one tugboat behind the ship, attached to it by a line. This tugboat acts as a brake to slow down and stop the large ship. Another tugboat can be near the bow of the ship, at the port or starboard side, depending on which side the captain of the assisted ship wants to moor. This second tugboat is attached to the side of the ship by a line, allowing the tug to push or pull the boat in the desired direction.

Tugboats are also used for towing. They can move a floating object with no power of its own, such as a barge, or a "dead ship," a ship that is not under its own power and is moved from one location to another. A typical towing situation would involve one tugboat with a towing cable attached from the stern of the tug to the barge or dead ship. A tandem tow is when one tugboat is towing two barges in a line. Barges can be used to move almost anything that a ship can, and the tugboats move them from one place to another.

A tugboat's role in a construction project is more varied and complex. Typically, a tug assists in construction by moving small barges carrying the construction equipment from place to place on a construction site. The tugboat can also act as a crew boat so that the construction crew can get around at crew change time.

Whatever their tasks, tugboats are essential to the marine industry. These workhorses of the sea can move vessels hundreds, even thousands, of times their own size. These tenacious little boats offer a perfect example of why it is always best not to judge a book by its cover, or in this case, a boat by its size.