A more thorough explanation:

A register of ships is a record that is maintained by a customs collector. This record contains important information about commercial vessels such as the names of the ships and their owners. When a ship logs in with customs, it receives a certificate of registry which is added to the register of ships.

For example, if a shipping company wants to register their new vessel with customs, they will need to provide all the necessary information about the ship such as its name, owner, and other important details. Once the ship is registered, it will be added to the register of ships and will be given a certificate of registry.

The register of ships is an important document as it helps to keep track of all the commercial vessels that are operating in a particular area. It also helps to ensure that all the ships are properly registered and that they meet all the necessary safety and environmental standards.