Seakeeping ability or seaworthiness is a measure of how well-suited a watercraft is to conditions when underway. A ship or boat which has good seakeeping ability is said to be very seaworthy and is able to operate effectively even in high sea states.
A steamboat is a boat that is propelled primarily by steam power, typically driving propellers or paddlewheels. The term steamboat is used to refer to small steam-powered vessels working on lakes, rivers, and in short-sea shipping. The development of the steamboat led to the larger steamship, which is a seaworthy and often ocean-going ship.
Steamboats sometimes use the prefix designation SS, S.S. or S/S (for 'Screw Steamer') or PS (for 'Paddle Steamer'); however, these designations are most often used for steamships.
A steamship, often referred to as a steamer, is a type of steam-powered vessel, typically ocean-faring and seaworthy, that is propelled by one or more steam engines that typically move (turn) propellers or paddlewheels. The first steamships came into practical usage during the early 19th century; however, there were exceptions that came before. Steamships usually use the prefix designations of "PS" for paddle steamer or "SS" for screw steamer (using a propeller or screw). As paddle steamers became less common, "SS" is incorrectly assumed by many to stand for "steamship". Ships powered by internal combustion engines use a prefix such as "MV" for motor vessel, so it is not correct to use "SS" for most modern vessels.
As steamships were less dependent on wind patterns, new trade routes opened up. The steamship has been described as a "major driver of the first wave of trade globalization (1870–1913)" and contributor to "an increase in international trade that was unprecedented in human history".