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. Krabs' 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 (2000).
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 (currently since 1999).
When series creator Stephen Hillenburg died on November 26, 2018 from ALS Nickelodeon aired a tribute commercial with the words "Thank You Stephen Hillenburg for making every day the best day ever".