Scrooge is a grumpy old man who lived alone and hated Christmas. One night he was visited by three ghosts to show him what would happen if he didn't change his ways. The ghost of Christmas past showed him his past when he was having fun with his friends.
The ghost of Christmas present took him to Bob chrachits house and showed him what would happen to Tiny Tim (Bob chrachits son) if he didn't change his ways.
Finally, the ghost of Christmas future showed him what would happen in the future if he didn't change. Scrooge was scared so he decided to be happy and to be kind on Christmas.