Action Comics #1 is the 1938 comic book widely credited with introducing Superman and launching the superhero genre.
Published by Detective Comics, Inc. on April 18, 1938, with a cover date of June 1938, the issue featured Superman on its cover lifting a car. The character was created by writer Jerry Siegel and artist Joe Shuster, who had developed him over several years before selling the feature to the publisher.
Action Comics #1 was an anthology, not a Superman-only title. Its other contents included characters such as Zatara and Pep Morgan, but Superman quickly became its defining attraction. His costume, extraordinary powers, secret identity, and heroic mission established a template copied by many later comic-book characters.
A common mix-up is confusing the issue with Superman #1, published in 1939. Superman #1 was the first comic book devoted entirely to the character; Action Comics #1 was his first published appearance and the historic debut that made the character famous.