Stephen Hillenburg, the creator of the long running Nickelodeon cartoon Spongebob Squarepants, has passed away at 57. Hillenburg told fans last year that he had been diagnosed with ALS, or amyotrophic lateral sclerosis, a neurodegenerative disease that affects cells in the brain and spinal cord.

Hillenburg became fascinated with the ocean as child by watching Jacques Cousteau documentaries on television. He taught at the Orange County Marine Institute, then returned to school to study animation. After earning a master's degree in fine arts, he joined the Nickelodeon network and it was there that his idea for a series about a sponge who lived in a pineapple under the sea came to fruition. Spongebob made its debut on Nickelodeon in 1999.

Read more about Stephen Hillenburg here.