interpreting letters, numbers and symbols on container ships

Very rarely do I learn so much from just one article, and this is what I just did, reading about The Secret Language of Ships, or how to interpret the names, numbers and symbols on huge container ships. The names and symbols are not only for officials, they also tell tugboats all the information the pilots need to help steer a ship. I remember the Hastings singlehandedly rescuing our cruiseship just outside Melbourne, and one of our neighbours is a tugboat pilot and it’s simply amazing, what they can do.


The owner, name and flag of the ship is paintec at the stern. Here the owner is Hanjin, the ship’s name is Beijing, and it sails under the flag of Panama. The International Maritime Organization, or IMO, number is the ship’s identification. Over its lifetime, the owner, name, or flag may change, but the IMO never changes. It’s possible to look up the ship’s history and location using IMO.

The human-shaped dummies are there to deter pirates into thinking there are crew members on watch.


This ship has what is called a bulbous bow, a round shape at the bottom of the bow that reduces drag, increasing speed and fuel efficiency. When at sea, the bulb is underwater so it’s necessary to tell tugboats that information, so there is no accidental collison. The white symbols, the one that looks like a 5 without the top line and the circle with a cross, is used for that purpose. The 5-alike symbol says there’s a bulb and the circle-cross says there’s a bow thruster also equipped.


The white rectangle with yellow border tells pilots this is the place to board the ship. It’s called the pilot boarding mark and the tugboat will wait till the rope ladder and gangplank are deployed. On some boats there is no gangplank and the pilot climbs solely using a flimsy rope ladder. Makes them even more kickass. Negotiating a huge ship into a narrow port is already amazing.