"Classic" novel

Malcolm X, Wuthering Heights, A Tale of Two Cities, To Kill a Mockingbird, etc.  These are all examples of novels labeled as "Classics."  I think they are given this name for the fact that they are sold all around the world and loved by all readers overall.  Normally, classics are books that have been read before and are not traditionally new books for the era.  This is because they can only be labeled as classics once it has been known worldwide that the book is a good read.  It must be bought and loved by many customers and have a little part in the story for any kind of reader.