A kid comes home from school and tells his mom, "I've got a problem.at school. Little Johnny keeps using two words I don't understand - pussy and bitch".

Mom says "Oh, that's no big deal.  Pussy is a little cat like our Fluffy, and bitch is a female dog, like our Queenie."

He says thanks, but decides he better check with his dad. He heads to the workshop in the basement where he tells his dad, "Little Johnny at school is using words I don't know. I asked mom but I don't think she told me the real meaning."

Dad says "Son, I told you never to go to your mom with stuff like that. She just doesn't get it. What are the words?" The boy tells him. "Pussy and bitch."

Dad thinks for a minute and says "OK" let me show you. He pulls out an old Playboy magazine from the bottom drawer, grabs a marking pen and opens to the centerfold. Then he circles the pubic area, points and says, "Son, everything inside that circle is pussy."

"OK dad, so then what's a bitch?"

"That's everything outside the circle."