A sidewheeler is a type of steamboat that is powered by side-mounted paddle wheels instead of a propeller. In nautical terms, the sidewheeler is often referred to as a paddle steamer or paddle wheel steamer. Furthermore, the paddle boat is another word used commonly for a sidewheeler. Other words that have been used to describe this type of vessel include side-wheeler, riverboat and river steamer. In some regions, it is also known as a sternwheeler, although strictly speaking, this refers to a type of paddle steamer where the paddle wheel is mounted at the stern of the vessel. Despite the varied nomenclature, the sidewheeler remains a classic example of steamboat technology.