SpongeBob SquarePants is a fictional character and the protagonist of Nickelodeon's eponymous American animated television series. Voiced by Tom Kenny, he is characterized by his optimism and childlike attitude. SpongeBob is a denizen of Bikini Bottom, where he regularly gets into absurd and humorous scenarios.

SpongeBob was created and designed by Stephen Hillenburg, an artist and marine science educator. The character's name is derived from "Bob the Sponge", the host of Hillenburg's unpublished educational book The Intertidal Zone. He drew the book while teaching marine biology to visitors of the Ocean Institute during the 1980s. Hillenburg began developing a show based on the premise shortly after the 1996 cancellation of Rocko's Modern Life, which Hillenburg served as creative director. SpongeBob's first appearance was in the pilot, "Help Wanted", which premiered on May 1, 1999.

SpongeBob SquarePants has become popular among children and adults. The character has garnered a positive response from media critics and is frequently named as one of the greatest cartoon characters of all time.