Steamships are large boats powered by steam engines, which use steam generated from boiling water to move. They played a crucial role in transportation during the 19th and early 20th centuries, allowing for faster travel across oceans and rivers compared to sailing ships. These vessels were often made of iron or steel and could carry passengers and cargo. The invention of the steamship significantly impacted trade and travel, leading to the growth of cities and industries. Notable examples include the SS Great Britain, designed by Isambard Kingdom Brunel, which was one of the first iron steamships to cross the Atlantic.