In art and literature, realism expresses a message that depicts situations realistically, whereas romanticism illustrates messages by using fiction. Romanticism focuses on plot, hyperbole, metaphor and feeling. In contrast, realism focuses on characters, details, objectivity and separation of author and narrator.
Romanticism rebels against prior forms of writing and art by picking into feeling, belief, imagination and fantasy. It is a style that takes advantage of personal freedom and spontaneity, breaking the fourth wall between the reader and the author so that the author is free to comment on events within the story and play with the reader a little. Unusual, often supernatural, characters and forces act in romantic stories.
Realism is on the opposite end of the spectrum, focusing on details in an attempt to replicate the real world in text form. The author is separate from the world of the story and acts as an objective transcriptionist. The characters are normal, everyday people and the events of the plot are typically normal and have a distinct lack of supernatural or fantastical elements. Realism is a common choice for writers of literary fiction, because it focuses on characters and characterization. In realism, even time and place are meant to enforce the characterization and normalcy of the characters and events.