A Christmas Carol is an 1843 fictional novella written by famed English writer Charles Dickens. It tells the story of Ebenezer Scrooge, an old, selfish, and cold miser whose life is turned upside down when he's visited by three spirits: the Ghost of Christmas Past, the Ghost of Christmas Present, and the Ghost of Christmas Yet to Come.
Scrooge's late business partner, Jacob Marley, is actually the first ghost to visit him. Marley died on Christmas Eve seven years prior to the events of the story; he is chained with heavy chains and iron blocks as a punishment for his greed and his selfish deeds. Moreover, he is forced to forever roam the spirit world with no chance of redemption. Marley warns Scrooge that he, too, will suffer the same fate in the afterlife if he doesn't immediately change his ways.
Marley informs Scrooge that he will be visited by three ghosts: the Ghost of Christmas Past (to remind Scrooge of the past, when he was a lonesome boy and an enthusiastic young man), the Ghost of Christmas Present (to show him how the people who are closest to him live and to see what they and the town think of him), and the Ghost of Christmas Yet to Come (to show him one possible future, in which he dies a miserable and unloved old man).