The show's surreal humor and heavy-handed social commentary mark it as a descendant of Spongebob Squarepants, which it actually wound up becoming. When Rocko was cancelled, most of the animation/writing team responsible - including new director Stephen Hillenburg - went on to work on everyone's favorite sponge, and the rest is history.
Rocko's look is simple but distinctive, but Rocko's color was almost different. His trademark beige look was originally yellow, but a toy company looking to merchandise the show already had a yellow character, so they made Nick change the look.
Back at the start of Nickelodeon, the company outsourced most of its animation to other studios. Rocko's Modern Life was the first show to break that trend, with Nick working on most of the animation in-house. Games Animation was created in 1993 in an effort to do just that and became a standard for Rocko and shows like Ren & Stimpy and Hey Arnold! before being
Rocko might look like a kangaroo, but he's actually a wallaby. Creator Joe Murray originally got the idea for the show when he went to the zoo and saw a wallaby who looked confused by what was going on. Given that Rocko always seems overwhelmed by the world around him, it's safe to say that Murray held on to that moment.
The Rocko's Modern Life theme song is about as jumpy and colorful as the show itself, but by the show's second season, bigger names came in to sing it. The B-52s tagged in to sing the theme song until the show's cancellation in 1996.
Arnold and friends made their debut on Nickelodeon in 1996, but did you know that Arnold made his debut nine years earlier? Creator Craig Bartlett included the original Arnold in 1987 for a series of claymation shorts that aired during Sesame Street. Yes, you can see a clay version of Arnold play the flute and frolick in the snow.
Bartlett is also in some esteemed animation company through his family, since Matt Groening married Bartlett's sister Lisa. Groening also gave Bartlett some advice on character design, suggesting that he draw characters that could be recognized by silhouette or at a distance.
As the show entered its fifth season, Nickelodeon gave Bartlett the opportunity to make two movies; one for theaters and one for TV. Bartlett originally intended the upcoming Jungle Movie involving Arnold's lost parents to be the movie aired in theaters, but off of the strength of screen testing for "Arnold Saves The Neighborhood," Nick decided to turn it into Hey Arnold!: The Movie. The movie made $15 million worldwide - five times its $3 million budget - but was still considered a disappointment, and eventually led to Bartlett leaving the show before its cancellation in 2004.
Craig Bartlett used to work at Klasky/Cuspo, the studio Nickelodeon outsourced much of its animation to in the early years. His Hungarian boss Gabor Cuspo was the inspiration for Oskar Kokoshka, Arnold's Czechoslovakian neighbor. Unfortunately, Steven Viksten - the voice actor and writer on the show who voiced Oskar - passed away in 2015.
When recording the music for Hey Arnold: The Movie, Composer Jim Lang decided to ditch the synthesizer music the show was known for and bring in a full blown orchestra. The orchestra wound up costing him his whole paycheck for about twenty minutes of recording time, but he was very happy with how the music turned out.
Spongebob is easily one of the most iconic animated characters of all time, but he almost had a different name. Originally named Spongeboy, his name was changed because a company had already trademarked the name for a mop. Spongeboy even wore a green hat that was removed for eventual Spongebob.
The Spongebob Squarepants Movie was Spongebob's first trip to the big screen, but it was also meant to be the series finale. That is, until Nickelodeon ordered more episodes of the series after the film's success. Fan theories floating around the internet suggest that the movie ending with Spongebob as the manager of the Krusty Krab 2 and Plankton in jail mean that this is still the definitive ending and that everything up to this point (including the second film Sponge Out Of Water from 2015) happens before the events of the first movie. It's a convincing argument, but who knows?
Remember that green fish in the brown pants who always screamed "my leg"? The end credits of the episode "Patty Hype" revealed that his name is actually Fred.
The town of Bikini Bottom where the show takes place is actually located underneath a real island called Bikini Atoll, which itself was the site of nuclear tests by the United States in 1946. Could it be possible that all of the aquatic life on the show are just mutants born from toxic waste? A large number of fans seem to think so.
The show's grouchy comic foil was named after squids, but considering that he has only six tentacles, he's actually an octopus. Creator Stephen Hillenburg claims that the two legs that would've made Squidward an actual squid would've made him harder to animate, so they kept him to six and dooming him to never reach his full potential.
As the first Nicktoon ever made, the Rugrats are icons of animation. To this day, they're the only Nickelodeon characters with their own star on the Hollywood Walk of Fame and one of ten animated characters/franchises with that honor; the others being Bugs Bunny, Donald Duck, The Simpsons, Mickey Mouse, Tinker Bell, Woody Woodpecker, Shrek, Snow White, and Winnie The Pooh.
Angelica was an emotionally manipulative bully with her younger friends, but some believe it was because none of the other babies were real. A fan theory suggests that Tommy, Chuckie, Phil, Lill, Dil, and Susie were actually figments of Angelica's imagination brought about from schizophrenia. It's very morbid and probably not real, but it's an interesting theory.
Chuckie Finster's bright orange hair, purple glasses, and Saturn shirt are his trademark, but his look was apparently inspired by a young Mark Mothersbaugh, former member of Devo. Mothersbaugh also helped compose the music for this and many other cartoons over the years, including the sequel series All Grown Up and even Crash Bandicoot.
Voice actress E.G. Daily gave Tommy Pickles his voice from the second episode of the series on, and she's shown her commitment in some wild ways. In an interview with The Guardian, Daily revealed that she was in labor during one of her recording sessions. She gave birth to one of her two daughters very shortly after.
Everyone remembers the iconic giant lizard, but there was an ulterior motive to including him on the show. As an obvious analogue for Godzilla, Reptar was put on the show as a commentary on the ubiquity of Japanese culture in children's television.