Nines and sixes

I was golfing today and came to the conclusion that I don't know the difference between a six and a nine when viewed right side up or upside down. That doesn't make much sense, I know. Let me clarify; Like when the power ball numbers fall out of their little scrambler bubbler on tv, and the host calls out the numbers, 7, 9, 4, 22,6, et cetera, If I were the host, wouldn't know if the number was a six or a nine even if it had the little line there to help me. I looked in my golf bag and my clubs have the line to help distinguish whether the club is a nine iron or the six iron but honestly, I had to look at the loft to figure it out. If the clubs were exactly the same and one was a nine and one was a six each with the line to help me, I couldn't tell you if the line is on the top for the six or the top for the nine or the bottom of the nine and the bottom of the six. I still don't know the difference.