When to use MY and MS for a yacht?

The prefixes "MY" and "MS" are used to designate different types of vessels. "MY" stands for "Motor Yacht" and is used for yachts primarily powered by engines. In contrast, "MS" stands for "Motor Ship" and is typically used for larger commercial vessels or those that may carry cargo or passengers. When naming a yacht, use "MY" if it is a recreational motor yacht and "MS" if it fits the characteristics of a motorized commercial ship.