Suppose you have a cake. You hand out tickets to people so they can each get a piece. If you hand out a thousand tickets, either you're going to have to slice the pieces very, very thin, or a lot of people are just going to have worthless tickets. If you hand out just two, each person can have quite a bit of cake. The value of the tickets, then, depends a lot on how many you hand out.

That's basically what money is. It's a promise to pay from the government. You get the money and you can trade it with people in that country for stuff. And just like with the cake, if suddenly tons of people have money, either the money ends up being worth very little or most of the people with money get nothing for it.

A good example of this from history was Germany in 1922. Faced with a sagging economy and forced to pay massive debts as reparations for World War I, the government started printing money as fast as they could to meet these demands. Paper mills and printing presses were LITERALLY running as fast as they could night and day. Over a period of six months or so, the value of the German mark dropped 3.7 MILLION times! What you could once buy for a mark now cost four million marks. People literally lugged around suitcases full of money to pay bills. Absolutely crazy stuff.