A seaplane is a class of aircraft that can land, float, and take off on the water. Seaplanes that are also capable of taking off and landing on airfields are part of a subclass known as amphibious aircraft. Both are divided into two categories depending on their technological specs: flying boats and floatplanes. The former is far larger and able to carry much more weight. In the past, they were referred to as Hydroplanes, but the term has fallen out of favor and it’s instead applied to watercraft powered by motor. A seaplane is only capable of landing on quiet waters with minimum wave activity on it, and has special trouble during extreme weather. The aircraft's size, hull and weight are the decisive factors for the level of wave activity the design can withstand. Flying boats are more adept at handling more hostile waters and rest steadier while on the water compared to floatplanes.