The Hulk is a fictional superhero appearing in publications by the American publisher Marvel Comics and appeared in the debut issue of The Incredible Hulk (May 1962). In his comic book appearances, the character is both the Hulk, a green-skinned, hulking and muscular humanoid possessing a vast degree of physical strength, and his alter ego Dr. Robert Bruce Banner, a physically weak, socially withdrawn, and emotionally reserved physicist. The two exist as independent dissociative personalities, and resent each other.
The original Hulk was shown as grey and average in intelligence who roamed aimlessly and became annoyed at "puny" humans who took him for a dangerous monster. Shortly after becoming the Hulk, his transformation continued turning him green, coinciding with him beginning to display primitive speech, and by Incredible Hulk #4 radiation treatments gave Banner's mind complete control of the Hulk's body. While Banner relished his indestructibility and power, he was quick to anger and more aggressive in his Hulk form, and, while he became known as a hero alongside the Avengers, his increasing paranoia caused him to leave the group, believing he would never be trusted.
Originally, the Hulk was shown as simple minded and quick to anger. The Hulk generally divorces his identity from Banner's, decrying Banner as "puny Banner." From his earliest stories, the Hulk has been concerned with finding sanctuary and quiet and often is shown reacting emotionally to situations quickly. Grest and Weinberg call Hulk the "dark, primordial side of Banner's psyche." Even in the earliest appearances, Hulk spoke in the third person. Hulk retains a modest intelligence, thinking and talking in full sentences. In the 1970s, Hulk was shown as more prone to anger and rage, and less talkative.