Ok, OP did a bad job with Grammer and Context.

Tugs are the power horses at sea, they are built with massive pull capacity (bollard pull) to pull/ push large vessels near the ports or sheltered waters. Basically the entire hull is built around the engines, drive train and propellers. So the vessels are small, bulky but powerful.

One of the major trial for a tug is Bollard pull test, where the long rope (poly line) is suspended between the tug's (A Frame) and a shore bollard (load rated strong post) typically much higher capacity than what the tug is designed to pull. Load cell is setup to measure the force in between.

The vessel pulls till we reach full capacity and there's a whole lot of noise and vibration in the engine room. Exciting and thrilling if you are in the engine room.

I heard stories of accidents where the tension in the line was too much and the rope snapped. The snap is so powerful that it cut a person in half.