The term "vessel" is used to describe any boat, ship, or other craft designed or used for travel on, in, through, or immediately above the water. Vessels are classified in several ways based on a specific characteristic.

All vessels are classified as either pleasure craft or non-pleasure vessels (sometimes referred to as "commercial vessels" or "work vessels"). According to the Safe Boating Guide, "a pleasure craft is any boat used only for pleasure activities like fishing, water sports, and entertaining friends. It also includes a boat used for subsistence hunting and fishing or for the necessities of daily life.". A non-pleasure or commercial vessel is one that "is used for work or commercial activities."

Vessels can also be classified based on their mode of propulsion:

Power-Driven Vessel       

This includes any vessel propelled by machinery. Typically this is an internal combustion or electric engine. Power-driven vessels come in all sizes, from a personal watercraft to a 30 metre luxury cruiser.

Sailing Vessel   

Any vessel under sail provided that propelling machinery, if fitted, is not being used.

Human Powered Vessel      

Any vessel propelled by a manual propelling device such as a set of oars or a paddle.