If you ask a scientist what pi is, he'll tell you it equals 3.14159..
 If you ask a mathematician, he'll tell you pi equals the circumference of a circle divided by its diameter..
If you ask an engineer, he'll say "Pi? Well, it's about 3, but we'll call it 4 just to be safe.."
But if you ask a kid, he’ll ask if he can have ice cream with it...!