How are books classified as classics? Are classics are simply written in other centuries, in older times? Or is it because they contain themes and character archetypes that are repeated in many books? I have seen in many stories that there were tragic love stories (Romeo and Juliet) and coming of age tales (The Catcher in the Rye). I think literary references are made to classics through themes, motifs, and character archetypes.
Themes have been repeated, although it doesn't go to say that specific books sprouted them. In the Catcher in the Rye by J.D. Salinger, a reoccurring theme is coming of age (growing up) and innocence. Holden Caulfield, the main character, is afraid to grow up, constantly rejecting the adult world and thinking it is "phony" (he uses that word many times). That is why he can be described as immature; Holden is unable to be responsible and his inquiry of where the ducks in Central Park went in the winter shows he has no desire to become an adult. He is obsessed with saving adolescence and preventing children, for example, his sister Phoebe, from growing up and facing the "phoniness" of the adult world. Lost of innocence is big deal for Holden and you can see that when he tries to erase the naughty words off of Phoebe's elementary school. He believes that children are innocent (and should remain that way) because they were not corrupt like adults(or at least the people around his age he was acquainted with), who had bias views on the world and society. In Holden's mind, anyone that was a kid was not a phony, like his sister and childhood friend, Jane Gallagher. Coming of age tales have been written before, such as Stephen Chbosky's The Perks of Being a Wallflower and even J.K. Rowling's Harry Potter series, because those are all books in which the main characters undergo adventures (use that word loosely) and develop as a human being.
Character archetypes seemed to stem from classics. In Wuthering Heights, Heathcliff can be referred to as the "misunderstood villain" for he is a seemingly bad person but actually, his actions were not always pure evil - he is a very messed up person due to ill-treatment from Hindley and having his love, Catherine, taken away from him. Some modern misunderstood villains include Scar, from the movie The Lion King and Darth Vader from Star Wars. I understand that those examples are characters from movies, but the point is that classics influence fiction in modern times.
The most known motif is the tragic love story. Romeo and Juliet set up a theme that would be used for many, many, many years to come. It's a theme that many different, amazing stories can be created from. The Hunger Games Trilogy by Suzanne Collins is a modern saga in which Peeta and Katniss' relationship are followed throughout (although their love was not the main point of the story). The movie Titanic is another tragic love story, and because of that theme in the story, it made the movie all the more tear-jerking and moving (that may have been the only reason that movie was so sad. You know, besides people sinking to their unpredicted fate).
In conclusion, I believe classics can be classified as "classics" and belong in that section in the library because fiction today use them as references and influences. Classic literature contains many themes, character archetypes, and motifs that hold for interesting stories. Stories that have such impact on books and movies today can considerably be called "classics".