Why is it called a hot water heater? If the water is already hot, why do we need to heat it? Why is it called tuna fish? We don't say hamburger cow, ham pig, or chicken bird. Exactly who decided it was sheep we were supposed to count to fall asleep? Why is it that a small child will never ask a question until you are in the middle of an important telephone conversation? Why do people ask "are we there yet?" when the car is still moving down the highway? What was the greatest thing before the invention of sliced bread? Feel free to add more.