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."
Stephen Hillenburg stopped making new episodes in 2002 to work on Bob Esponja, la película (2004). Nickelodeon had eight unaired episodes, and aired two or three a year.
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).
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".
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.