After Rocko was cancelled in 1996, he began developing SpongeBob SquarePants into a television series that same year and in 1997, a seven-minute pilot was pitched to Nickelodeon. Hillenburg joined Nickelodeon in 1992 as an artist on Rocko's Modern Life. Many of the series's ideas originated in The Intertidal Zone, an unpublished educational comic book Hillenburg created in 1989 to teach his students about undersea life. By 2019, it had generated over $13 billion in merchandising revenue. Its popularity made it a media franchise, the highest rated Nickelodeon series, and the most profitable property for Paramount Consumer Products. As of 2019, the series is the fifth-longest-running American animated series. The series received worldwide critical acclaim, and has gained popularity by its second season. It chronicles the adventures of the title character and his aquatic friends in the underwater city of Bikini Bottom. SpongeBob SquarePants is an American animated television series created by marine science educator and animator Stephen Hillenburg that premiered on Nickelodeon as a sneak peek after the 1999 Kids' Choice Awards on May 1, 1999, and officially premiered on July 17, 1999.
