of the texts. This includes narratives about self-identity, life and death, and individuality. Genre There are no distinguishable differences in genre styles between YA fiction and adult fiction. Some of the most common YA genres include contemporary fiction, fantasy, romance, and dystopian. Hybrid genres are also common in YA. New adult fiction Problem novels Social problem novels or problem novels are a sub-genre of literature focusing and commenting on overarching social problems. They are typically a type of realistic fiction that characteristically depict contemporary issues such as poverty, drugs, and pregnancy. Published in 1967, S.E. Hinton's The Outsiders is often credited as the first problem novel. Following this release, problem novels were popularized and dominated during the 1970s. Librarian Sheila Egoff described three reasons why problem novels resonate with adolescents: They depict real situations that the readers are experiencing so they have "therapeutic value" They are interesting, new and foreign to those not experiencing these issues, They feature mature story lines which appeal to a child's desire to grow up. A classic example of a problem novel and one that defined the sub-genre is Go Ask Alice by Anonymous (pseudonym for Beatrice Sparks) published in 1971. Go Ask Alice is written in first-person as the diary of a young girl who experiences a lot of problems while growing up. In order to cope with her problems, the protagonist begins experimenting with drugs. Modern examples of problem novels include Speak by Laurie Halse Anderson, Crank by Ellen Hopkins, and The Perks of Being a Wallflower by Stephen Chbosky. Boundaries between children's, young adult, and adult fiction The distinctions among children's literature, young adult literature, and adult literature have historically been flexible and loosely defined. This line is often policed by adults who feel strongly about the border. At the lower end of the age spectrum, fiction targeted to readers aged 8–12 is referred to as middle grade fiction. Some novels originally marketed to adults are of interest and value to adolescents, and vice versa, as in the case of books such as the Harry Potter series of novels. Some examples of middle grade novels and novel series include the Percy Jackson & the Olympians series by Rick Riordan, The Underland Chronicles by Suzanne Collins, and Diary of a Wimpy Kid by Jeff Kinney. Some examples of young adult novels and novel series include the Harry Potter series by J. K. Rowling,