Whaling is the hunting of whales primarily for meat, oil, and blubber. Its earliest forms date to at least circa 3000 BC. Various coastal communities have long histories of subsistence whaling and harvesting beached whales. Industrial whaling emerged with organized fleets in the 17th century; competitive national whaling industries in the 18th and 19th centuries; and the introduction of factory ships along with the concept of whale harvesting in the first half of the 20th century.