An American comic book is a thin periodical originating in the United States, on average 32 pages, containing comics. While the form originated in 1933, American comic books first gained popularity after the 1938 publication of Action Comics, which included the debut of the superhero Superman. This was followed by a superhero boom that lasted until the end of World War II. After the war, while superheroes were marginalized, the comic book industry rapidly expanded and genres such as horror, crime, science fiction and romance became popular. The 1950s saw a gradual decline, due to a shift away from print media in the wake of television and the impact of the Comics Code Authority. The late 1950s and the 1960s saw a superhero revival and superheroes remained the dominant character archetype throughout the late 20th century into the 21st century. Some fans collect comic books, helping drive up their value. Some have sold for more than US$1 million. Comic shops cater to fans, selling comic books, plastic sleeves ("bags") and cardboard backing ("boards") to protect the comic books. An American comic book is also known as a floppy comic. It is typically thin and stapled, unlike traditional books.American comic books are one of the three major comic book industries globally, along with Japanese manga and the Franco-Belgian comic books. Source: Wikipedia (en)