Since you did not clarify which novel or non-fiction work related to the Titanic, let me give you a broad overview of some of the most significant passengers aboard the ship:
John Jacob Astor--This real estate mogul millionaire from the U.S. was refused a spot on the lifeboats but witnesses said he calmly accepted his fate.
Isador and Ida Straus-- The owners of Macy's, the department store chain, both elected to stay with each other aboard the ship rather than be separated.
Benjamin Guggenheim-- The wealthy industrialist went down with the ship dressed in his finest, like a true 'gentleman'.
J. Bruce Ismay--The managing director for the White Star line claimed a place on one of the life rafts and survived the sinking.
Margaret Brown-- Known as "the unsinkable Molly Brown," she was considered to be 'new money' as the wife of a rich mine owner. She threatened to have the Quartermaster who was in charge of their lifeboat, thrown overboard if he did not row back and help look for survivors.
Captain Edward Smith-- The Titanic was supposed to be the captain's final command before retirement. He went down with the ship.
Wolf, Allan. The Watch that Ends the Night. New York: Candlewick, 2011.