Which is better: toupee or wig?

Does wearing toupees mean you are losing hair and you are trying to hide that fact? What is the difference between a toupee and a wig? Why do people wear toupees? How many famous people have worn toupees and how common is it for man to wear toupees. What colors do you get them in and what are they made of? Would you wear a toupee even if you had hair?