|Real name||Jack Napier|
|Debut||Batman #1 (June 1940)|
|Created by||Jerry Robinson, Bill Finger, Bob Kane|
|Played by||Jack Nicholson, Mark Hamill, Heath Ledger, others|
The Joker is a supervillain widely considered to be Batman's archenemy. The Joker is a master criminal with a clown-like appearance,and a violent sociopath who murders people for his own amusement, a vicious, calculating and psychopathic killer. He was described as a homicidal maniac by Batman, and was admitted into Arkham Asylum many times. He was Batman's deadliest enemy and a constant and dangerous one of the Justice League, also being one of the founders of the Injustice League.