Boats have a wide variety of shapes, sizes and construction methods due to their intended purpose, available materials or local traditions. Canoe-type boats have been used since prehistoric times and various versions are used throughout the world for transportation, fishing or sport. Fishing boats vary widely in style partly to match local conditions. Pleasure boats include ski boats, pontoon boats, and sailboats. House boats may be used for vacationing or long-term housing. Small boats can provide transport or convey cargo (lightering) to and from large ships. Lifeboats have rescue and safety functions. Boats can be powered by human power (e.g. rowboats), wind power (e.g. sailboats) and motor power (e.g. propellor-driven motorboats driven by gasoline or diesel engines).
Dugouts are the oldest type of boats found by archaeologists, and boats have served as transportation since the earliest times. Circumstantial evidence, such as the early settlement of Australia over 40,000 years ago, findings in Crete dated 130,000 years ago, and findings in Flores dated to 900,000 years ago, suggest that boats have been used since prehistoric times. The earliest boats are thought to have been logboats, and the oldest boats found by archaeological excavation date from around 7,000–10,000 years ago. The oldest recovered boat in the world is the Pesse canoe, a dugout made from the hollowed tree trunk of a Pinus sylvestris and constructed somewhere between 8200 and 7600 BC. This canoe is exhibited in the Drents Museum in Assen, Netherlands. Other very old dugout boats have also been recovered. Rafts have operated for at least 8,000 years. A 7,000-year-old seagoing reed boat has been found in Kuwait. Boats were used between 4000 and 3000 BC in Sumer, ancient Egypt and in the Indian Ocean.
Boats played an important role in the commerce between the Indus Valley Civilization and Mesopotamia. Evidence of varying models of boats has also been discovered at various Indus Valley archaeological sites. Uru craft originate in Beypore, a village in south Calicut, Kerala, in southwestern India. This type of mammoth wooden ship was constructed using teak, without any iron, and had a transport capacity of 400 tonnes. The ancient Arabs and Greeks used such boats as trading vessels.
Boats can be categorized into three main types: