John Borland "Jack" Thayer III (December 24, 1894 – September 20, 1945) was a first-class passenger on RMS Titanic who survived after the ship struck an iceberg and sank on April 14, 1912.
Aged 17 at the time, he was one of only a handful of passengers to survive jumping into the frigid, cold ocean.
He later wrote and privately published his recollection of the sinking.