A steamboat is a boat that is propelled primarily by steam power, typically driving propellers or paddlewheels. 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.

The term steamboat is used to refer to smaller, insular, steam-powered boats working on lakes and rivers, particularly riverboats. As using steam became more reliable, steam power became applied to larger, ocean-going vessels.

John Fitch (January 21, 1743 – July 2, 1798) was an American inventor, clockmaker, entrepreneur and engineer. He was most famous for operating the first steamboat service in the United States. The first boat, 45 feet long, was tested on the Delaware River by Fitch and his design assistant Steven Pagano.