SpongeBob is depicted as being an optimistic, cheerful, naïve, enthusiastic yellow sea sponge residing in the undersea city of Bikini Bottom alongside an array of anthropomorphic aquatic creatures. He works as a fry cook at a local fast food restaurant, the Krusty Krab, to which he is obsessively attached.[12] At work, SpongeBob answers to Eugene Krabs, a greedy, miserly crab who shows SpongeBob favor,[13] alongside his ill-tempered, hateful, snobbish next-door neighbor Squidward Tentacles. His favorite hobbies include his occupation, jelly-fishing, karate (albeit at an elementary level, with Sandy Cheeks as his sensei),[14] relentless fandom of superheroes Mermaid Man and Barnacle Boy, and blowing bubbles.[15]

He is often seen hanging around with his best friend Patrick, who lives on the same street as SpongeBob two doors down. However, SpongeBob's varying intelligence, unlimited optimistic cheer, and irritating behavior often leads him to perceive the outcome of numerous endeavors and the personalities of those around him as happier and sunnier than they often actually are; for instance, he believes that Squidward enjoys his company in spite of the fact that he clearly loathes him.[16] A recurring gag in several episodes is SpongeBob's extremely poor "boating" (driving) ability and his repeated failures to pass his road test at Mrs. Puff's Boating School.[17] He lives in an iconic pineapple with his pet snail Gary.