Wonder Man is a fictional character, a superhero in the Marvel Comics universe. He was created by Stan Lee and Jack Kirby, and is a member in long standing of The Avengers.

Simon Williams was born the son of a rich family, and inherited the family's company and fortune. Despite this, he embezzled money from the company and was caught. The supervillain Baron Zemo found the desperate Williams and offered him a chance to escape, by transforming him into the ionically-powered Wonder Man. Wonder Man joined the Avengers on Zemo's behalf, but ultimately turned on Zemo and was apparently killed in doing so. He actually remained in a deathlike state of suspended animation for years, during which time the android Ultron based the brain of an android of his own, the Vision, upon that of Wonder Man. Simon's brother, Eric, became the supervillain called the Grim Reaper , and the process that had empowered Simon was also used to empower the villain Count Nefaria.

Wonder Man was eventually revived and finally joined the Avengers full-time, becoming close friends with his teammate, the Beast. With his zest for life, he became an actor in addition to a superhero, and was one of the major members of the West Coast Avengers team. Wonder Man eventually came to accept the Vision as his "brother". However, the Vision was dismantled and rebuilt as an emotionless machine, and his marriage to Wanda Maximoff, the Scarlet Witch, was annulled. Wonder Man later became romantically involved with the Witch. However, the West Coast Avengers soon disbanded, and Simon was subsequently disintegrated in battle with the alien Kree. The Scarlet Witch was eventually able to restore Simon to life with her chaos magic, and in the process brought back the Grim Reaper, who at the time had been a ghost. Simon and Wanda resumed their relationship, but eventually drifted apart.

Wonder Man (DC):

In the Superman comics, there is a super-hero called Wonder Man. He comes to rival Superman, possessing the same powers as he, minus his weaknesses. His popularity surpassed Superman which left him depressed, feeling like a has-been.

It was later revealed that Wonder Man used to be Ajax, one of Superman's duplicate robots (that he used for help or hiding his identity). Ajax got kidnapped by alien invaders who turned him into a real living being, while still having his bionic super-powers. The invaders wanted to use him to remove Superman so that he would no longer be in their way for their attack. Wonder Man, not being evil, thwarted their plan with Superman when he learnt their full intentions. After the aliens' defeat, Superman offered Wonder Man (who revealed him his secret) to fight at his side but the aliens installed a death-mechanism in him that was triggered to kill him within a week. Wonder Man died, and then laid in a grave which said that he was born a robot, but died a human.