To be clear, SpongeBob isn’t the kind of sponge you use to wash dishes. “That’s a cellulose sponge,” Hillenburg says. “Sponges are a colonial animal, which basically means they’re a bunch of cells who work together in order to survive.” Do they have a brain or a heart? “No,” he says, patiently. “They have no nervous system. The behavior is, they sit and siphon water.” Fortunately for us, SpongeBob’s got a little more going on. He has cool pals: Patrick Star and Sandy, the surfing squirrel. SpongeBob is a creative, enterprising young sponge, and kids will learn a lot from his failures and foibles. But the best thing about the show is how Hillenburg’s passion for the sea comes shining through.