The Bat-Signal is a distress signal device appearing in the various interpretations of the Batman mythos. It is a specially modified Klieg searchlight with a stylized symbol of a bat attached to the light so that it projects a large Bat emblem on the sky or buildings of Gotham City. In the stories, the signal is used by the Gotham City Police Department as a method of contacting and summoning Batman to their assistance in the event of a serious crisis and as a weapon of psychological intimidation to the numerous villains of Gotham City.
Batman's secret identity is Bruce Wayne, an American billionaire, playboy, philanthropist, and owner of Wayne Enterprises. After witnessing the murder of his parents as a child, he swore revenge on criminals, an oath tempered by a sense of justice. Wayne trains himself both physically and intellectually and crafts a bat-inspired persona to fight crime. An American cultural icon and one of the most popular superheroes ever. Batman operates in the fictional Gotham City, relying on his genius intellect, physical prowess, martial arts abilities, detective skills, science and technology, vast wealth, provocation of fear and intimidation, and an indomitable will. The character was created by artist Bob Kane and writer Bill Finger and first appeared in Detective Comics #27 (May 1939).