Action Comics is the comic book series that will forever be known for introducing the world to 
Superman.  Teenagers 
Jerry Siegel[?] and 
Joe Shuster launched their creation with 
Action Comics #1 in June of 
1938.  The character of the dynamic Man of Steel was an instant hit, and he permanently changed the medium of 
comic books and 
comic strips.  
Action Comics was soon followed by the Superman comic book series, and a wealth of other comics starring numerous costumed superheroes.
(See Superman for more information about the Man of Steel.  This entry should deal more with the history of the comic book itself.)
 
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