What is Normal?

What is the definition of being normal? Who decides who is normal and who isn't? Are celebrities the normal ones in the world or are the homeless? A college student hardly fits into the "normal" category when put up against an middle adult who is now in the working world. A college student stays up late drinking and sleeps late, occasionally goes to class, and survives on a diet of pizza and beer... is that considered normal? But then you have the elderly population who have 50 cats and eats all their food pureed, could that be normal? Why do we care if we are normal or not. I am happy being considered crazy and weird... because I don't really want to be placed into a "normal" category. Do You?