Giant-Man is the alias used by several superheroes appearing in American comic books published by Marvel Comics, usually in association with the alias Ant-Man. Hank Pym first appeared as Giant-Man in Tales to Astonish #49, though he had appeared multiple times before, first in #27 as a civilian, and in #35 as Ant-Man. Regardless of iteration, Giant-Man usually has the power to enlarge to enormous sizes. Giant-Man also frequently overlaps with the alias Goliath.
Hank Pym, the first Giant-Man, with the Wasp, appeared in many superheroes stories published in the serial Tales to Astonish and later, The Avengers.
Bill Foster later became the second Giant-Man and the Black Goliath.
Raz Malhotra debuted in The Astonishing Ant-Man #4 as the third Giant-Man and later as one of the supporting characters of the regular series, joining Scott Lang's Ant-Man Security Solutions.
Henry "Hank" Pym was the original version of Giant-Man. He used the super hero identity after joining the Avengers with the Wasp, Iron Man, Thor and the Hulk. He has also used other aliases like Ant-Man, Goliath, Yellowjacket, and Wasp.
William "Bill" Foster was the second version of Giant-Man who originally went by Black Goliath.
The Skrull Criti Noll utilized the abilities of Hank Pym / Giant-Man during the Secret Invasion storyline.
Raz Malhotra is the third major version of Giant-Man. The character, created by Nick Spencer and Brent Schoonover, first appeared in Ant-Man Annual #1 (July 2015). He is an Indian American computer technician whose former field of study was in artificial intelligence at the time when Hank Pym started to rid the world of them. Lured by the supervillain Egghead, he freed himself from Egghead's control with the help of Pym. Some time after Pym's apparent death, Scott Lang gives Malhotra a Giant-Man uniform. After he is summoned to the portal city of Pan, Giant-Man joins the New Agents of Atlas to help protect the newly formed city. He later begins a relationship with Isaac Ikeda, the "Protector of Pan".
Scott Lang is the second major version of Giant-Man in the Ultimate Marvel universe.
The Ultimate Marvel universe features the Giant-Men, a group of characters who have size-shifting powers and special jumpsuits that can grow with them. The Giant-Men are reserve members of S.H.I.E.L.D. and consist of Giant-Men (such as David Scotty and Peter) as well as the alternately named Goliaths and Giant-Women.