RMS Titanic was a passenger liner that sank in the North Atlantic Ocean on 15 April 1912 after colliding with an iceberg during her maiden voyage from Southampton to New York City. The sinking of Titanic caused the deaths of 1,514 people in one of the deadliest peacetime maritime disasters in history. She was the largest ship afloat at the time of her maiden voyage. One of three Olympic class ocean linersoperated by the White Star Line, she was built between 1909–11 by the Harland and Wolff shipyard in Belfast. She carried 2,224 people.

Her passengers included some of the wealthiest people in the world, as well as over a thousand emigrants from Britain, Ireland, Scandinavia and elsewhere seeking a new life in North America. The ship was designed to be the last word in comfort and luxury, with an on-board gymnasium, swimming pool, libraries, high-class restaurants and opulent cabins. She also had a powerful wireless telegraph provided for the convenience of passengers as well as for operational use. Though she had advanced safety features such as watertight compartments and remotely activated watertight doors, she lacked enough lifeboats to accommodate all of those aboard. Due to outdated maritime safety regulations, she carried only enough lifeboats for 1,178 people – a third of her total passenger and crew capacity.

After leaving Southampton, England on 10 April 1912, Titanic called at Cherbourg in France and Queenstown, Ireland before heading westwards towards New York. On 14 April 1912, four days into the crossing and about 375 miles south of Newfoundland, she hit an iceberg at 11:40 pm (ship's time; UTC-3). The glancing collision caused Titanic's hull plates to buckle inwards in a number of locations on her starboard side and opened five of her sixteen watertight compartments to the sea. Over the next two and a half hours, the ship gradually filled with water and sank. Passengers and some crew members were evacuated in lifeboats, many of which were launched only partly filled. A disproportionate number of men – over 90% of those in Second Class – were left aboard due to a [url=http://en.wikipedia.org/wiki/Women_and_children_first_(saying)]"women and children first"[/url] protocol followed by the officers loading the lifeboats. Just before 2:20 am Titanic broke up and sank bow-first with over a thousand people still on board. Those in the water died within minutes from hypothermia caused by immersion in the freezing ocean. The 710 survivors were taken aboard from the lifeboats by the RMSCarpathia a few hours later.

The disaster was greeted with worldwide shock and outrage at the huge loss of life and the regulatory and operational failures that had led to it. Public inquiries in Britain and the United States led to major improvements in maritime safety. One of their most important legacies was the establishment in 1914 of the International Convention for the Safety of Life at Sea (SOLAS), which still governs maritime safety today. Many of the survivors lost all of their money and possessions and were left destitute; many families, particularly those of crew members from Southampton, lost their primary bread-winners. They were helped by an outpouring of public sympathy and charitable donations. Some of the male survivors, notably the White Star Line's chairman, J. Bruce Ismay, were accused of cowardice for leaving the ship while people were still on board, and they faced social ostracism.

The wreck of the Titanic remains on the seabed, gradually disintegrating at a depth of 12,415 feet (3,784 m). Since its rediscovery in 1985, thousands of artefacts have been recovered from the sea bed and put on display at museums around the world. Titanic has become one of the most famous ships in history, her memory kept alive by numerous books, films, exhibits and memorials.