Batman made his debut in Detective Comics #27, which collectors believe first appeared on newsstands on this day in 1939. Since his debut, Batman has undergone many drastic changes, but somehow our collective perception remains pure.
The origins of Batman are complicated. After the massive success of Superman, comic book publishers were hungry for more costumed adventurers, and National Publications (which would become DC) commissioned a superhero from Bob Kane, who had previously been at Fleischer Studios. He made a proposal for a winged, red-suited avenger with blonde hair and a domino mask called Bird-Man. He enlisted the aid of Bill Finger, a writer he had befriended at a cocktail party, and Finger smartly urged Kane in a different, far better direction.