SteamshipA 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 1800s; 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).
Mississippi| unit_pref = Imperial | area_footnotes = | area_magnitude = | area_total_km2 = 125,443 | area_total_sq_mi = 48,430 | area_land_km2 = 121,607 | area_land_sq_mi = 46,952 | area_water_km2 = 3,940 | area_water_sq_mi = 1,521 | area_water_percent = 3 | area_rank = | dimensions_footnotes = | length_km = 545 | length_mi = 340 | width_km = 275 | width_mi = 170 | elevation_footnotes = | elevation_m = 90 | elevation_ft = 300 | elevation_point = | elevation_max_footnotes = | elevation_max_m = 246.
RiverA river is a natural flowing watercourse, usually a freshwater stream, flowing on the surface or inside caves towards another waterbody at a lower elevation, such as an ocean, sea, bay, lake, wetland, or another river. In some cases, a river flows into the ground or becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to by names such as creek, brook, and rivulet. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities, a stream is defined by its size.
Marine propulsionMarine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems. Human-powered paddles and oars, and later, sails were the first forms of marine propulsion.