Batman is a DC Comics superhero created by artist Bob Kane and writer Bill Finger in 1939. In Detective Comics #27 (May 1939) he made is debut also known as "The Bat-Man", "The Batman", "The Caped Crusader", "The Dark Knight", and "The World's Greatest Detective." Batman's secret identity is Bruce Wayne, an American billionaire playboy and philanthropist. Having witnessed the murder of his parents as a child, he swore revenge on criminals. Wayne trains himself both physically and intellectually in order to fight crime. Batman operates in the fictional American Gotham City, assisted by various supporting characters including his crime-fighting partner, Robin, his butler Alfred Pennyworth, the police commissioner Jim Gordon, and occasionally the heroine Batgirl. He fights an assortment of villains such as the
Joker, Harley Quinn, the Penguin, the Riddler, Two-Face, Ra's al Ghul, Scarecrow, Poison Ivy, and Catwoman, among others. Unlike most superheroes, he does not possess any superpowers; he makes use of intellect, detective skills, science and technology, wealth, physical prowess, martial arts skills, an indomitable will, fear, and intimidation in his continuous war on crime.
Batman became a very popular character soon after his introduction and gained his own comic book title, Batman, in 1940. As the decades wore on, differing interpretations of the character emerged. The late 1960s Batman television series used a camp aesthetic which continued to be associated with the character for years after the show ended. Various creators worked to return the character to his dark roots, with varying results. The comic books of this dark stage culminated in the acclaimed 1986 miniseries The Dark Knight Returns by Frank Miller, as well as Batman: The Killing Joke by Alan Moore and Arkham Asylum: A Serious House on Serious Earth, among others. The overall success of Warner Bros.' live-action Batman feature films have also helped maintain public interest in the character.
Batman is a founding member of the Justice League of America.
In "The Griffin Equivalency," before going into Raj's office, Leonard suggests to Sheldon that he smile instead of giving comments. Sheldon gives it a practice run, but his first try mimics the Joker, smiling as he plots to kill Batman. The effect is enough to frighten Leonard and Howard.
In "The Hofstadter Isotope," Howard and Sheldon get into an argument over All-Star Batman and Robin the Boy Wonder #8. Sheldon needs it for his Robin collection & Howard needs it for his Batman collection.
In "The Irish Pub Formulation," Sheldon tells Leonard that he can't keep a secret, even though both Alfred and Batman have their secrets. Sheldon: You know I can't keep a secret! Alfred knows that Barbara Gordon is Batgirl. Which I've now just told to Batman! See, I cannot keep a secret!
In "The Justice League Recombination," Howard gets to wear the Batman costume in their Justice League of America|Justice League costume team.
In "The Griffin Equivalency," Sheldon has to be pleasant to Rajesh Koothrappali who is going to be in People Magazine. Sheldon tries to put on a pleasant simile which is compared to the Joker, Batman's arch enemy.
In "The Bat Jar Conjecture," Leonard buys Sheldon a Batman cookie jar, before he tells him that he has been kicked off their Physics Bowl Team.
In "The Bad Fish Paradigm," Leonard is trying to get a secret out of a drugged Sheldon. In his stupor, Sheldon claims that the secret is that "I'm Batman."
In "The Speckerman Recurrence," Sheldon tells Leonard that when he faces his high school bully, Batman (i.e. Sheldon) will have his back.
In "The Shiny Trinket Maneuver," Sheldon is seen reading a Batman comic book in the bathroom.
In "The Grasshopper Experiment," Sheldon pulls out his Justice League membership card that is signed by Batman.
In "The Holographic Excitation," Sheldon suggests that he and Amy dress up as Batman and Robin.
In "The Celebration Experimentation," Sheldon reveals that he hates his birthday due to his sister and her friends lying to him about Batman coming to their sixth birthday party. To make amends for it, the guys get Adam West to be at the party. Along the way, they all get into a minor argument over who was the best live-action Batman: West himself (pointing out that he had a sense of humor, had his own muscles instead of fake ones, and never had to say "I'm Batman"), Michael Keaton, Christian Bale, George Clooney, or Val Kilmer.
In "The Dependence Transcendence", the Flash appears to a sleeping Sheldon and tells him that all superheroes use energy drinks and take performance enhancing chemicals. The Hulk uses steroids. Batman stalks the night looking for fights because he drinks scotch. He gives Sheldon his first energy drink free because he invested his money in Marvel Comics, the rival comic book company.