Theme Definition: the main idea or message that the author wishes to convey to the reader
A theme is the message that the author wants the reader to understand by the time they have finished reading. Themes are typically important lessons about life that the reader can connect with in a tangible way. A good theme will leave a reader making connections to the characters and their own life. A theme will sometimes be controversial or have no clear answer, which can prompt the reader to ask deeper questions about the world around them.
The theme is not always explicitly stated; sometimes, the reader must infer the lesson from context, dialogue, or events. The theme often reveals the true intentions of the characters throughout the story, and authors develop theme to tie the importance of their characters and the events of the work together. For example, in A Christmas Carol by Charles Dickens, the readers can infer that loving money too much can lead to a miserable, lonely existence, as exhibited by Scrooge. It is only through the visits of three ghosts that Scrooge comes to understand that money is not the true key to happiness in life, and it is with this understanding that he finds redemption and contentment with his family and his employee, Bob Cratchit.
Be sure to check out our article, "Themes, Symbols, and Motifs"!