Harley Quinn was created by Paul Dini and Bruce Timm and first appeared in "Batman: The Animated Series" in the episode "Joker's Favor." She was voiced by Arleen Sorkin.
Harley Quinn made her first appearance in DC Comics in "The Batman Adventures" #12, bridging her transition from animation to comics.
As part of DC's New 52 reboot, Harley's design and backstory were updated, including a more punk-inspired look.
Harley Quinn was portrayed by Margot Robbie in the 2016 film "Suicide Squad," gaining mainstream movie recognition.
Harley Quinn was the lead character in "Birds of Prey," a standalone film highlighting her story beyond the Joker.