A steamboat or steamship, sometimes called a steamer, is a ship in which the primary method of propulsion is steam power
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

, typically driving propeller
A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid is accelerated behind the blade. Propeller dynamics can be modeled by both Bernoulli's...

s or paddlewheel
Paddle steamer
A paddle steamer is a steamship or riverboat, powered by a steam engine, using paddle wheels to propel it through the water. In antiquity, Paddle wheelers followed the development of poles, oars and sails, where the first uses were wheelers driven by animals or humans...

s. Steamships usually use the prefix designation
Ship prefix
A ship prefix is a combination of letters, usually abbreviations, used in front of the name of a civilian or naval ship.Prefixes for civilian vessels may either identify the type of propulsion, such as "SS" for steamship, or purpose, such as "RV" for research vessel. Civilian prefixes are often...

 SS, S.S. or S/S.

The term steamboat is usually used to refer to smaller steam-powered boats working on lakes and rivers, particularly riverboat
A riverboat is a ship built boat designed for inland navigation on lakes, rivers, and artificial waterways. They are generally equipped and outfitted as work boats in one of the carrying trades, for freight or people transport, including luxury units constructed for entertainment enterprises, such...

s; steamship generally refers to larger steam-powered ships, usually ocean-going, capable of carrying a (ship's) boat.

1807    Robert Fulton's first American steamboat leaves New York City for Albany, New York on the Hudson River, inaugurating the first commercial steamboat service in the world.

1809    Robert Fulton files a patent for improvements to steamboat navigation

1811    The first steamboat to sail the Mississippi River arrives in New Orléans, Louisiana.

1849    Regular steamboat service from the west to the east coast of the United States begins with the arrival of the SS ''California'' in San Francisco Bay, 4 months 22 days after leaving New York Harbor.

1854    The San Francisco steamer sinks, killing 300 people.

1865    The steamboat ''Sultana'', carrying 2,400 passengers, explodes and sinks in the Mississippi River, killing 1,700, most of whom are Union survivors of the Andersonville and Cahaba Prisons.

1962    The Old Bay Line, the last overnight steamboat service in the United States, goes out of business.