A sailing ship is a sea-going vessel that uses sails mounted on masts to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing square-rigged or fore-and-aft sails. Some ships carry square sails on each mast—the brig and full-rigged ship, said to be "ship-rigged" when there are three or more masts. Others carry only fore-and-aft sails on each mast, for instance some schooners. Still others employ a combination of square and fore-and-aft sails, including the barque, barquentine, and brigantine.
Early sailing ships were used for river and coastal waters in Ancient Egypt and the Mediterranean. The Austronesian peoples developed maritime technologies that included the fore-and-aft crab-claw sail and with catamaran and outrigger hull configurations, which enabled the Austronesian expansion into the islands of the Indo-Pacific. This expansion originated in Taiwan c. 3000 BC and propagated through Island Southeast Asia, reaching Near Oceania c. 1500 BC, Hawaii c. 900 AD, and New Zealand c. 1200 AD. The maritime trading network in the Indo-Pacific dates from at least 1500 BC. Later developments in Asia produced the junk and dhow—vessels that incorporated features unknown in Europe at the time.
European sailing ships with predominantly square rigs became prevalent during the Age of Discovery (15th to 17th centuries), when they crossed oceans between continents and around the world. In the European Age of Sail, a full-rigged ship was one with a bowsprit and three masts, each of which consists of a lower, top, and topgallant mast. Most sailing ships were merchantmen, but the Age of Sail also saw the development of large fleets of well-armed warships. The many steps of technological development of steamships during the 19th century provided slowly increasing competition for sailing ships — initially only on short routes where high prices could be charged. By the 1880s, ships with triple-expansion steam engines had the fuel efficiency to compete with sail on all major routes — and with scheduled sailings that were not affected by the wind direction. However, commercial sailing vessels could still be found working into the 20th century, although in reducing numbers and only in certain trades.