I see SpongeBob on ice-cream trucks a lot, and I've got bootleg SpongeBob merchandise from Mexico.
I pitched the idea that SpongeBob and Patrick learn a swearword. Everyone said no. I couldn't even use a bleep. So I used a dolphin sound instead.
SpongeBob is a complete innocent - not an idiot. SpongeBob never fully realizes how stupid Patrick is. They're whipping themselves up into situations - that's always where the humor comes from.
I wanted to create a small town underwater where the characters were more like us than like fish. They have fire. They take walks. They drive. They have pets and holidays.
When you set out to do a show about a sponge, you can't anticipate this kind of craze. We just try to make ourselves laugh, then ask ourselves if it's appropriate for children.
I knew I wanted to create a character who was nerdy and kind of square, so when I drew a square sponge, everything came together. And originally his name was SpongeBoy, but there we couldn't use that for trademark reasons.