The Hulk is a fictional superhero appearing in American comic books published by Marvel Comics. The character was created by Stan Lee and Jack Kirby, and first appeared in The Incredible Hulk #1 (May 1962). Throughout his comic book appearances, the Hulk is portrayed as a large green humanoid that possesses superhuman strength and invulnerability, attributes that grow more potent the angrier he becomes.Hulk is the alter ego of Bruce Banner, a socially withdrawn and emotionally reserved physicist who physically transforms into the Hulk under emotional stress and other specific circumstances at will or against it; these involuntary transformations lead to many complications in Banner’s life. When transformed, the Hulk often acts as a dissociated personality separate from Banner.

Source: https://en.wikipedia.org/wiki/Hulk_(Comic)