This category should only contain other categories. Galleries should be in the corresponding categories instead. Files should be in a parent or subcategory.
The general format for category titles is "<name of ship> (ship, <year>)". <year> is the year the ship was completed, see Category:Ships by year of manufacture for further information.
"<name of ship> (ship, <year>)" is a naming convention rather than a disambiguation rule. "(ship, <year>)" is added even if there is no other category named "<name of ship>". The "<name of ship>" may already mean ship.
Submarines use "<name> (submarine, <year>)" and tugs/towboats use "<name> (tugboat, <year>)". All other types are identified by category:Ships by type.
Fishing ships display their license number. Categories for these have the format "<license number> <name> (ship, <year>)" (see Category:Fishing vessels by license number).
If there are several ships with the same name built in the same year, the place where the ship was built/location of the shipyard is added: "<name of ship> (ship, <year>, <place>)".
In the rare case that there are several ships with the same name built the same year at the same place, the yard number is also added: "<name of ship> (ship, <year>, <place>, <yard number>)".
Sample: "E. R. Sterling (ship, 1883)" uses {{DISPLAYTITLE:Category:''E. R. Sterling'' (ship, 1883)}}. On the category description page, you will notice that this formats the page title as Category:E. R. Sterling (ship, 1883).