After you get far away from your starting island and travel into the open sea you’ll start to see many Pirate Ships. These are really dangerous because if they decide to hit you and you’re on a Raft — you are dead. You can craft and command you own ship but it takes a lot of resources to craft a Ship, especially Wood.
Pirate Ships always have a commander, a set of people who do things around the Ship and fighters that control the Cannons. If you do not have other people, you can also hire A.I. players to control the Cannons for you.
When Ships get destroyed they will drop item crates into the Sea which you can then claim. These crates can often have things such as Gold and resources so they are a great thing to pick up if you’ve just started out sailing on your Raft and have nothing.