Diddy Kong is one of the most notable characters in the Mario franchise. Although relatively unimportant to the mainstream Mario titles, he is one of the main characters in the Donkey Kong Country subseries and has appeared in many Mario spinoffs, as well as the Super Smash Bros. crossover fighting games.
Diddy is the little monkey buddy and best friend of Donkey Kong, referred to by Cranky as a hero-in-training. As with all Kongs, Diddy loves bananas. He's sometimes a bit of a slacker, but nonetheless a determined and eager young hero. In addition to using his quick speed and prehensile tail, he can fly real high with his jetpack on, and with his pistols out, he's one tough Kong. He'll make you smile when he plays his tune, but Kremlings should beware, as he is after them.
Although Diddy is typically thought of as DK's sidekick, he is the main protagonist in Donkey Kong Country 2, in which he teams up with his girlfriend Dixie to rescue DK from the Kremlings, and also had his own spin-off kart racer, Diddy Kong Racing.
Diddy, as well as the other new characters from the SNES and Nintendo 64 Donkey Kong games, is notable in that he was created not by Nintendo of Japan, but by the British-based Rareware.