Angel is a Marvel Comics character, first appearing in X-Men #1.
William Kenneth Worthington III started growing wings when he was in mid-adolescence. In several months the wings went from tiny nublets to their full span (sixteen feet, tip to tip). He found that his wings were extremely flexible, so he folded them and taped them under his clothes to avoid being persecuted by people prejudiced against mutants. One night, however, there was a fire in his college dorm room. Worthington donned a blonde wig and a nightshirt so everyone would think he was an angel, then used his ability to fly to save the people in the building. It was that night that he resolved to use his mutant powers to help people. Shortly thereafter, he was recruited to join the original X-Men team by Professor Charles Xavier.
Worthington served as a member of the X-Men for several years, then went on to work with various other groups (Defenders, Champions, X-Factor). Angel was wounded in battle during his time with X-Factor, resulting in his wings becoming crippled and infected. Because of his injuries, doctors amputated Worthington's wings, effectively making him an ordinary human. The man fell into a deep depression. He changed his will, leaving his considerably vast fortune (inherited from his parents) to X-Factor, and set out to commit suicide. He would not be successful.
Before he could kill himself, Angel was kidnapped by the mutant known as Apocalypse. Apocalypse used his vast genetic knowledge to cause Angel's wings to regrow in a new form. Whereas they had been made of bright, white feathers, they were now composed of an organic-metallic compound. As a result of the genetic manipulation, Angel's skin also became a nice shade of blue. Apocalypse didn't stop there; he wiped Worthington's mind and turned him into one of his personal assassins. Angel adopted the new name, Death. Eventually Death fought with X-Factor and was defeated. His defeat shocked him into regaining his free will and his memory, but he had suffered extensive psychological trauma. He flew off in a rage, and for several years he lived his life alone.
When Worthington finally returned to X-Factor, he did so under the new name Archangel. Archangel retained all of the new strength and agility that Apokalypse's genetic manipulation had granted him, though, due to extensive damage caused by a battle with Sabertooth, the metallic make-up of his wings has been destroyed. He's back to the feathers. Archangel is currently a member of X-Factor.