One of the notable aspects of 19th and 20th century American short stories is their diversity. Writers like Edgar Allan Poe in the 19th century were masters of the macabre. His stories, such as 'The Tell - Tale Heart', had a dark and psychological depth. In the 20th century, Ernest Hemingway's short stories were known for their sparse style. For example, 'Hills Like White Elephants' is a story full of subtext about relationships and difficult decisions. Another important feature was the exploration of the American identity. Many stories dealt with the immigrant experience, the changing social classes, and the impact of industrialization.