TMNT and TMHT

Who are the TMHT?

TMHT, standing for Teenage Mutant Hero Turtles, are the English version of the Teenage Mutant Ninja Turtles.

What’s the difference between them?

There is no difference between them in structure/plot, but the word ‘ninja’ was censored is some representations of the turtles, and replaced with ‘hero’.

Why was this censored?

The reason was never announced officially, but it is presumed that the word ‘ninja’ was deemed to have connotations of violence, and may have influenced children into behaving dangerously.

Which TMNT universes were censored?

The cartoon, the films, and the live action sitcom, Ninja Turtles; the Next Mutation.
The Mirage and Image comics never were though, probably because they were meant for an older audience, and neither were the Archie comics, mostly because there was no need to.

What was omitted from these?

The titles of the cartoon and the live action show were changed as detailed above, resulting in slightly different theme tunes, with different singers. Also, in the cartoon, scenes with Michaelangelo’s nunchukus are usually cut out partially or completely, so the plot often lacked key points.
The film’s titles were not changed, but in these also, Michaelangelo’s nunchukus are edited out in the following ways:

TMNT 1 During the fight with the Foot at April O’Neil’s apartment, Mikey twirls his ‘chuks in a mini-performance for a Foot member, but this is missed out in the English version, and so the film jumps from his laughing, to Donatello leaping over a Foot member to begin the battle.
Near the end of the film, instead of showing Splinter knocking the Shredder off balance with a pair of nunchukus, the camera pans upwards to only show the top half of Splinter’s body, and not his weapons.
TMNT 2

When Keno arrives at April’s apartment in order to discover if the turtles do live there, she explains the existence of a pair of nunchukus on her coffee table by saying she uses them herself, and promptly hits herself with them....except in the English version which omits the scene.

TMNT 3 At the beginning of the film, during the dance routine, Mikey is not given any screen time by himself as the others are. The American version includes his own solo performance with ‘chuks, and a punch bag.
Throughout the film, any time Mikey uses his nunchukus, they are edited, most noticeably when the turtles are fighting Walker and the Japanese warriors, and Mikey is not shown, or filmed only from the waist up to prevent sightings of his weapons.