Okay kiddo, have you ever played with a toy that had wheels? Well, imagine a really big toy with wheels that moves along the water instead of on the ground. That's a ship!
Now, some ships have a special part called a cam. This is like a bump or a hump on the ship's surface. When the ship moves through the water, the cam makes the ship wobble a little bit from side to side.
Why would anyone want their ship to wobble like that? Well, it turns out that the wobbling motion actually helps the ship move faster and use less fuel. It's like a secret trick that makes the ship work better!
So, in short, a cam ship is just a ship with a special bump on it that helps it move better through the water. Cool, huh?