The characters in SpongeBob SquarePants were created by artist, animator and former marine biologist Stephen Hillenburg. In addition to the series' main cast, various celebrities have voiced roles in SpongeBob SquarePants. Notably, Ernest Borgnine and Tim Conway voice the roles of recurring characters Mermaid Man and Barnacle Boy respectively, while others have taken a one off part.
Creator Stephen Hillenburg initially conceived the characters for SpongeBob SquarePants in 1984, while he was teaching and studying marine biology at what is now the Orange County Ocean Institute. During his period, Hillenburg became fascinated in animation, and wrote a comic book entitled The Intertidal Zone starring various anthropomorphic forms of sea life, many of which would evolve into SpongeBob SquarePants characters, including "Bob the Sponge", who was the co-host of the comic and resembled an actual sea sponge as opposed to SpongeBob.
SpongeBob SquarePants (Tom Kenny) is the main protagonist of the series. He is a optimistic, energetic, lively sea sponge who physically resembles a kitchen sponge and lives in a pineapple-shaped house. He is often shown in the series working at The Krusty Krab as a fry cook. SpongeBob's hobbies in the show include practicing karate with Sandy and catching jellyfish. He attends Mrs. Puff's Boating School, but has never passed; his lack of a driver's license serves as a running gag throughout the series.
SpongeBob was originally named "SpongeBoy" by the series creators, but it was later changed due to trademark issues. Green and purple were early color choices for the character before his classic yellow was chosen.
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