SpongeBob SquarePants is an American animated comedy television series created by marine science educator and animator Stephen Hillenburg for Nickelodeon. The series chronicles the adventures of the title character and his aquatic friends in the fictional underwater city of Bikini Bottom. Being the fifth-longest-running American animated series, its high popularity has made it a media franchise. It is the highest rated series to air on Nickelodeon as well as the most profitable property for ViacomCBS Consumer Products, having generated over $13 billion in merchandising revenue as of 2019.

Many of the series' ideas originated in The Intertidal Zone, an unpublished educational book that Hillenburg created in 1989 to teach his students about undersea life. He began developing SpongeBob SquarePants into a television series in 1996, and in 1997, a seven-minute pilot was pitched to Nickelodeon. The network's executives wanted SpongeBob to be a child in school, but Hillenburg preferred SpongeBob to be an adult character. He was prepared to "walk out" on Nickelodeon and abandon the series, but he compromised by creating Mrs. Puff and her boating school, so that SpongeBob could attend school as an adult.

Nickelodeon held a preview for the series in the United States on May 1, 1999, after it aired the 1999 Kids' Choice Awards. The series officially premiered on July 17, 1999. It has received worldwide critical acclaim since its premiere and had gained enormous popularity by its second season. The series has inspired three feature films: 'The SpongeBob SquarePants Movie (2004), Sponge Out of Water (2015), and Sponge on the Run (2020), as well as a fourth one, Search for SquarePants, that released in theaters on December 19, 2025. Two spin-off series, Kamp Koral: SpongeBob's Under Years and The Patrick Star Show, premiered in 2021. Two additional spin-off movies for the other characters have premiered on Netflix: Saving Bikini Bottom: The Sandy Cheeks Movie (2024), Plankton: The Movie (2025), and a third untitled Patrick Star-focused movie is expected to premiere on Netflix in the near future.