The show's creator, Stephen Hillenburg, was a marine biologist. When he pitched the show to Nickelodeon, he brought a fish tank into the boardroom, and explained what was living inside. He then placed a cartoon drawing of SpongeBob into the tank and said "This is SpongeBob, the star of your new show."
Mr. Krab's birth date is November 30, 1942. SpongeBob's is July 14, 1986, as revealed on each characters driver's license, in dream sequences, in season one, episode fifteen, "Sleepy Time/Suds".
Stephen Hillenburg stopped making new episodes in 2002, to work on The SpongeBob SquarePants Movie (2004). Nickelodeon had eight unaired episodes, and aired two or three a year.
Out of all the Nicktoons to air in the 1990s, this is the only one still in production, and the longest running one (as of September 2016).
To create SpongeBob's distinctive laugh, Tom Kenny hits his throat with his hand repeatedly while saying, "Ahh."
Squidward makes various references to 11 minutes. Every episode lasts about 11 minutes 30 seconds.
The Krusty Krab's siren is identical to the siren used in The Shawshank Redemption (1994), which also featured Clancy Brown.
Season one was the only season to use traditional cel animation. In season two, they started to ink, paint, and edit it digitally.
Over the years, many fans of the show have asked Tom Kenny to lend SpongeBob's voice to their voice-mail and answering machines. In an interview, he joked that these custom messages might be more common than the factory-default voice.
Frequently, a French accented-voice comes on to note a passage of time. It's an homage to Jacques-Yves Cousteau, a leading influence on Stephen Hillenburg and his interest in marine biology.
SpongeBob's first words were, "May I take your order?" Before this, in his mother's womb, his first words were, "Krabby Patty," and followed this by eating the same Krabby Patty his mother ate.
According to concept art, the "Krabby Patty" was originally going to be called the "Barnacle Burger".
SpongeBob SquarePants was the first cartoon on Nickelodeon to have over 200 episodes.
Tom Kenny said he came up with the voice of SpongeBob SquarePants, when he heard an angry dwarf yelling.
Karen is named after Stephen Hillenburg's wife. Her voice actress, Jill Talley is Tom Kenny's wife.
While Stephen Hillenburg was a director for Rocko's Modern Life (1993), he showed the show's writer, Martin Olson, a comic book called "The Intertidal Zone", that Hillenburg drew in college. Olson loved it, and suggested that Stephen re-write it as an undersea cartoon series, which became SpongeBob SquarePants.
Patrick was noticeably bigger in season one. As the seasons progressed, he began to slim down.
Tom Kenny voices SpongeBob SquarePants, Gary The Snail, and the narrator. He also plays the live-action Patchy The Pirate.
In South Korea, SpongeBob is called "Square Square Sponge", or, more often "Square Square Sponge Song." The title song needed four words to match the music, and most children refer to him the second way.
SpongeBob was originally named SpongeBoy, but that name was already trademarked for a cleaning product.
The German title of this show is "SpongeBob Schwammkopf" which means "SpongeBob SpongeHead".
SpongeBob's last name is SquarePants, but all of his relatives are round, except Stanley, who is part square, as it was revealed in season five, episode twenty, "Banned in Bikini Bottom/Stanley S. SquarePants".
Worms are portrayed as dogs, and sea snails (or Gary in this case) are portrayed as cats. Gary says "meow".
SpongeBob has played his nose as a flute in SpongeBob SquarePants: Patrick SmartPants/SquidBob TentaclePants (2005), SpongeBob SquarePants: Best Day Ever/The Gift of Gum (2006), and SpongeBob SquarePants: Drive Happy/Old Man Patrick (2018).
Despite being a cartoon for children, many episodes feature violence and adult humor.
Squidward inks in SpongeBob SquarePants: Giant Squidward/No Nose Knows (2008), SpongeBob SquarePants: Spot Returns/The Check-Up (2017), and SpongeBob SquarePants: My Leg!/Ink Lemonade (2018). He also inks in The SpongeBob Movie: Sponge Out of Water (2015).
The voice actors for Mermaid Man and Barnacle Boy also played the main characters on McHale's Navy (1962).
Season one, episode fourteen, "SB-129", and season three, episode ten, "Krusty Krab Training Video", feature the credits on a space, and a black background, respectively, instead of the traditional underwater background.
The show, which premiered in May 1999, is the second-to-last Nicktoon of the 1990s (the last was Rocket Power (1999). It is also the longest-running Nicktoon, spanning three decades: the 1990s, 2000s, and 2010s.
"Squidward's Suicide," posted on YouTube, depicts Squidward committing suicide. The episode allegedly depicts scenes of "violence and gore", as well as quick flashes of dead children and other disturbing imagery. A story that provides background for the video states that the video was created in 2005, and was viewed by a select test screening at Nickelodeon. Show Writer Casey Alexander said that the episode was a "100% hoax."
In Mexico, the show is only called "Bob Esponja", which means Sponge Bob in Spanish.
The signal flags hanging on the front of The Krusty Krab do not spell a word. The third signal flag (from left to right, facing the front door) doesn't exist in international nautical code. The first, second, fourth, and fifth are R, I, U, and K, although the U is only "right-side-up" if the flags are read from right-to-left. Inside Mr. Krabs' office is _, I, R, and M. The _ has no letter associated with the flag.
In season two, episode three, "Big Pink Loser", we learn that Patrick's last name is Star.
Clancy Brown and Bill Fagerbakke have both played corrupt prison guards. Brown played Captain Byron Hadley in The Shawshank Redemption (1994). Fagerbakke played Karl Metzger in Oz (1997).
The show has had 2 Christmas specials: SpongeBob SquarePants: Christmas Who? (2000) and SpongeBob SquarePants: It's a SpongeBob Christmas! (2012).
SpongeBob appears in every episode in some way. His alternate universe counterpart appears in SpongeBob SquarePants: The Algae's Always Greener/SpongeGuard on Duty (2002).
Ernest Borgnine voices Mermaid Man. In real life, Borgnine was married to Ethel Merman.
Squidward's name is a joke on Edward. Technically, however, it is a neologism meaning "Towards the Squid".
Sandy's line "We could be tighter than bark on a tree" led one internet humorist to animate a series of parodies in which this surreal expression is repeatedly dropped in among equally surreal characters and situations.