Megan Thurow, chapter 11, question 7

After reading this chapter, the thing that stuck out to me the most was the fact that money is not backed by anything worth value. I remember talking in class about how American money is not actually backed by gold but I thought it was interesting that money from other countries is the exact same. Money from all places is just paper and it seems like it really shouldn't  be worth anything too special. I'm still some what confused by how we know how much the dollar is worth compared to say, the Russian ruble. I'd like to learn more about that if we get the chance :)