This week is a hard week for, we learned the value of money, I get a lot of new knowledge from this lesson. In twenty years ago, the value of money is different frim now, the money is always change, just like if you wants to use 15$ to buy a pizza in 1960, you can buy a lot of pizza, but in 2013, you can not use 15$ to buy a lot of pizza, the value are also influenced by inflation. I think this lesson is very hard to understand, I still need to pat more attention on this lesson.