This document discusses various appendages attached to ship hulls including rudders, skegs, stabilizers, bilge keels, sacrificial anode systems, propellers, bow thrusters, and bulbous bows. It describes the purpose and characteristics of each appendage in 1-3 sentences. Rudder types include balanced, semi-balanced skeg, full skeg, and spade rudders. Propeller types are fixed pitch, variable pitch, ducted, and skeg propellers. Bow thrusters assist in ship maneuvering. A bulbous bow reduces drag and increases speed and stability.