Flip-Flop of God: Marvel goes back and forth over whether or not the Hulk has ever accidentally killed someone during his city destroying rampages. This led to a notable Retcon at least once; the Hulk was sent into space for the Planet Hulk storyline because a fight between him and the Thing inadvertently caused the deaths of over twenty people. This was later retconned into severe injuries, which made the whole "shoot him into space" thing into retroactive Disproportionate Retribution.
The Hulk was originally colored grey. However, the printing technology of the time kept turning him green. Over time, Stan Lee decided to keep green as the Hulk's signature color.
Early in the Hulk's adventures, Lee would frequently alternate between calling the Hulk's Secret Identity "Bob Banner" and "Bruce Banner". When informed of this mistake by fans, Lee decided to establish that Banner's full name was Robert Bruce Banner.
When Hulk was first introduced in 1962, the writers at Marvel Comics struggled with many aspects of his characterization and visual appearance before eventually settling on his now-iconic portrayal as a misunderstood green-skinned monster with child-like intelligence who appears whenever Bruce Banner gets angry. As a result, in his earliest appearances, the Hulk was a brutish grey-skinned monster with roughly normal intelligence who appeared when the sun went down. Years down the line, the writers decided to explain the discrepancy by retroactively declaring that the "Grey Hulk" was actually a different character from the more iconic "Savage Hulk", and his consciousness came from a different aspect of Bruce Banner's shattered psyche. Later, other writers further explored this aspect of the character by toying with the idea that there are even more incarnations of the Hulk, each with its own slightly different personality. This resulted in some of the most popular and acclaimed stories in the character's history, like Planet Hulk (starring his "Green Scar" persona) and Immortal Hulk (starring his "Devil Hulk" persona).
Throw It In!: When the Hulk first fought the Fantastic Four, Stan Lee famously goofed and referred to Banner as Bob Banner throughout the issue. That's why, from then on, Banner's full name has been Dr. Robert Bruce Banner.
According to this source, Peter David originally intended for the Hulk's temporary girlfriend Marlo Chandler to be a prostitute like her roommate who helps set her up with the Hulk. This was during the time he had adopted the persona of Joe Fixit and was working as a mob enforcer in Las Vegas. However he was told he couldn't do that and so changed Marlo into an aerobics instructor and her roommate a nurse, though when reading the comic it is clear that there is little explanation why a nurse would be associated with a mob boss and said mob boss would think an aerobics instructor would be the best choice to spend time with Fixit.
, Peter David originally intended for the Hulk's temporary girlfriend Marlo Chandler to be a prostitute like her roommate who helps set her up with the Hulk. This was during the time he had adopted the persona of Joe Fixit and was working as a mob enforcer in Las Vegas. However he was told he couldn't do that and so changed Marlo into an aerobics instructor and her roommate a nurse, though when reading the comic it is clear that there is little explanation why a nurse would be associated with a mob boss and said mob boss would think an aerobics instructor would be the best choice to spend time with Fixit.