Short answers, pulled from the story.
James Cook was a British Royal Navy officer, explorer, and cartographer who lived from 1728 to 1779. He led three voyages of exploration to the Pacific and Southern Oceans between 1768 and 1779, completing the first recorded circumnavigation of New Zealand's main islands and leading the first recorded European visits to Australia's east coast and the Hawaiian Islands.
James Cook was killed on the 14th of February 1779 at Kealakekua Bay during his second visit to Hawaii, when a dispute with Native Hawaiians turned violent. After Hawaiians stole one of his boats, Cook tried to recover it by kidnapping the king Kalaniʻōpuʻu, and in the fighting that followed Cook and four marines were killed, along with 17 Hawaiians.
James Cook was born on the 7th of November 1728 in the village of Marton in the North Riding of Yorkshire, the second of eight children of a Scottish farm labourer. He worked briefly as a shopboy in Staithes before becoming a merchant navy apprentice in the Walkers' coal trade fleet at Whitby, where he taught himself navigation and astronomy.
Cook's first voyage of 1768 to 1771 publicly aimed to observe the 1769 transit of Venus from Tahiti, while secret orders sought the hypothesised continent Terra Australis. His second voyage from 1772 to 1775 set out to determine whether Terra Australis existed, and his third voyage from 1776 searched for a North-West Passage linking the north Pacific to the Atlantic.
Many Hawaiians considered Cook to be the Polynesian god Lono because his arrival coincided with the Makahiki, a harvest festival of worship for Lono. Some scholars believe the mast formation, sails, and rigging of his ship HMS Resolution resembled significant artefacts used in that season of worship, and Hawaiians prostrated themselves before Cook when he first stepped ashore.
Cook led three expeditions across tens of thousands of miles of mostly uncharted ocean without losing a single ship, producing charts of Newfoundland more accurate than Royal Navy charts made a century later. He pioneered scurvy prevention, for which the Royal Society awarded him the Copley Gold Medal, and he tested Larcum Kendall's K1 chronometer, helping solve the longitude problem.
Cook is contested because his voyages paved the way for British colonisation, and critics such as the Native Hawaiian scholar Haunani-Kay Trask highlight violent encounters, introduced diseases, and lands claimed without consent. Around the 250th anniversary of his first voyage, memorials in Australia, New Zealand, Canada, and Hawaii were vandalised, with public calls for their removal.