Life is rather uncertain nowadays as anything can happen at any time and we would be caught off guard. That’s also one way to describe the current economy at this stage. With the world’s economy expanding and expanding there have been more crashes as the years go by and they are becoming more frequent and some say at any moment one could happen.

So you are left with a situation in which the money you currently own, fiat money: the dollar bills & coins, will become worthless and you cannot even buy anything you need to survive on a day to day basis. In this situation, people will have to resort to a system of bartering like in the stone ages. I guess if you have a lot of stuff with value you can trade that would be great, but a majority of people don’t have such a stash. Things can get ugly real fast.
   
Therefore, in such a doomsday situation you have to come up with a situation in which you can trade with people in order to survive. There are two solutions I can come up with, either using precious metals such as Gold & Silver or using Cryptocurrency. Considering that fiat currency is useless, Cryptocurrency might raise in value so that it can be useful as a means of trade as long as the Internet still exists which will most likely be the case.