The Joker is a fictional character

Character (arts)

A character is the representation of a person in a narrative work of art . Derived from the ancient Greek word kharaktêr , the earliest use in English, in this sense, dates from the Restoration, although it became widely used after its appearance in Tom Jones in 1749. From this, the sense of...

, a comic book

Comic book

A comic book or comicbook is a magazine made up of comics, narrative artwork in the form of separate panels that represent individual scenes, often accompanied by dialog as well as including...

 supervillain

Supervillain

A supervillain or supervillainess is a variant of the villain character type, commonly found in comic books, action movies and science fiction in various media.They are sometimes used as foils to superheroes and other fictional heroes...

 published by DC Comics

DC Comics

DC Comics, Inc. is one of the largest and most successful companies operating in the market for American comic books and related media. It is the publishing unit of DC Entertainment a company of Warner Bros. Entertainment, which itself is owned by Time Warner...

. He is the archenemy

Archenemy

An archenemy, archfoe, archvillain or archnemesis is the principal enemy of a character in a work of fiction, often described as the hero's worst enemy .- Etymology :The word archenemy or arch-enemy originated...

 of Batman

Batman

Batman is a fictional character created by the artist Bob Kane and writer Bill Finger. A comic book superhero, Batman first appeared in Detective Comics #27 , and since then has appeared primarily in publications by DC Comics...

, having been directly responsible for numerous tragedies in Batman's life, including the paralysis

Paralysis

Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

 of Barbara Gordon

Barbara Gordon

Barbara Gordon is a fictional character appearing in comic books published by DC Comics and in related media, created by Gardner Fox and Carmine Infantino...

 and the death of Jason Todd

Jason Todd

Jason Peter Todd is a fictional character that appears in comic books published by DC Comics. Jason first appeared in Batman #357 and became the second Robin, sidekick to the superhero Batman, when the previous Robin went on to star in The New Teen Titans under the moniker of Nightwing.Though...

, the second Robin

Robin (comics)

Robin is the name of several fictional characters appearing in comic books published by DC Comics, originally created by Bob Kane, Bill Finger and Jerry Robinson, as a junior counterpart to DC Comics superhero Batman...

. Created by Jerry Robinson

Jerry Robinson

Jerry Robinson is an American comic book artist best known for his work on DC Comics' Batman line of comics during the 1940s.He was inducted into the Comic Book Hall of Fame in 2004.-Career:...

, Bill Finger

Bill Finger

William "Bill" Finger was an American comic strip and comic book writer best known as the uncredited co-creator, with Bob Kane, of the DC Comics character Batman, as well as the co-architect of the series' development...

 and Bob Kane

Bob Kane

Bob Kane was an American comic book artist and writer, credited as the creator of the DC Comics superhero Batman...

, the character first appeared in Batman #1 (Spring 1940).

Throughout his comic book appearances, the Joker is portrayed as a master criminal whose characterization has varied.