- "Oh! Awesome! That's the Bat-Signal! That's your... oh. Shh. Sorry. That's your signal. That means we have to go now!"
- ―Barry Allen to Bruce Wayne[src]
The Bat-Signal, or Bat Signal is a specially modified searchlight with a stylized symbol of a bat attached to projects a large Bat emblem into the skies of Gotham City. The signal is used by Commissioner James Gordon as a method of contacting and summoning Batman to his assistance in the event of a serious crisis and as a weapon of psychological intimidation to the numerous crooks of Gotham City.
Batman v Superman: Dawn of Justice
Batman shined the Bat-Signal in the sky as a means to attract Superman to fight him.
Commissioner James Gordon shined the Bat-Signal as a means to summon Batman to help him.